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Nature of Energy
bull Energy is all around youo You can hear energy as
soundo You can see energy as
lighto You can feel it as wind and
heat
bull You use energy when youo hit a softballo lift your book bago compress a springo Burn fuel
States of Energy Kinetic and Potential Energy
bull Kinetic Energy is the energy of motion
bull Potential Energy is stored energy of position or chemical bonds
Nature of Energybull Energy is
involved wheno a bird flieso a bomb
explodeso rain falls from
the skyo electricity
flows in a wire
Kinetic Energybull The energy of motion is called
kinetic energybull The faster an object moves the
more kinetic energy it hasbull The greater the mass of a moving
object the more kinetic energy it has
bull Kinetic energy depends on both mass and velocity
Kinetic Energy
KE = frac12 mass x velocity2
What has a greater affect of kinetic energy mass or velocity Why
Potential Energybull Potential Energy is stored
energyoStored chemically in bonds of fuel
or food oStored as nuclear energy holding
subatomic particles together oOr stored because of the work done
on itbull Stretching a rubber bandbull Winding a watchbull Pulling an arrow back on a bowrsquos string
bull Lifting a brick high in the air
Gravitational Potential Energy
bull Potential energy dependent on height is called Gravitational Potential Energy (a form of mechanical energy)
Gravitational Potential Energy
bull If you stand on a 3-meter diving board you have 3 times the GPE than you had on a 1-meter diving board
bull GPE=Weight x Height
bull (pounds) x (feet)bull or (Newtons) x (meters)
bull GPE = (M)(Ag) (H)bull M=Kg Ag =98msec2H=m
Kinetic ndash Potential Energy Conversion
Cars are mechanically pulled to the peak which is the point of maximum potential energy the car has minimum kinetic energy As position is exchanged for speed potential is converted to kinetic energy
Ball slows down
Ball speeds up
Forms of Energy
bull The five main forms of energy areoHeatoChemicaloElectromagneticoNuclearoMechanical
Heat Energybull The internal motion of the
atoms is called heat energy because moving particles produce heat
bull Heat energy can be produced by friction
bull Heat energy causes changes in temperature and phase of any form of matter
Chemical Energy
bull Chemical Energy is required to bond atoms together
bull And when bonds are broken energy can be released or absorbed
bull Exothermic = energy released
bull Endothermic=energy absorbed
Chemical Energy
bull Fossil Fuels and our Food are forms of energy stored in chemical bondsbull The Energy came from nuclear
fusion on our Sun and was photosynthesized by plants and stored in plant and animal life
Formation of Fossil Fuels
bull Petroleum and Natural gas are both products of millions of years of decomposing Marine life both animal and plant
bull Coal is similar but mostly from terrestrial plant life
Where does Coal come from
Electromagnetic Energybull Electricity -- carried in
wiresbull Light -- Each of the colors
of light (ROY G BIV) represents a different amount of electromagnetic energy
bull X-rays amp Cosmic Raysbull TV amp Radio wavesbull Laser light
Nuclear Energybull When the nucleus
splits (Fission) nuclear energy is released in the form of heat energy and light energy
bull Nuclear energy is also released when nuclei collide at high speeds and join (Fusion)
bull MOST CONCENTRATED
Mechanical Energy
bull When work is done to an object it acquires energy The energy it acquires is known as mechanical energy
Mechanical Energy
bull When you kick a football you give mechanical energy to the football to make it move
Energy Conversionbull Energy can be changed from one form to another Changes in the form of energy are called energy conversions
bull Good Examples on Pages 418-419
Energy conversionsbull All forms of energy can be
converted into other formsoThe sunrsquos energy through solar
cells can be converted directly into electricity(Photovoltaic energy)
oGreen plants convert the sunrsquos energy (electromagnetic) into the bonds in starches and sugars (chemical energy) using Photosynthesis
Other energy conversions
oIn an electric motor electromagnetic energy is converted to mechanical energy
oIn a battery chemical energy is converted into electromagnetic energy
oMechanical energy of water falling can be converted to electrical energy in a generator
Hydroelectric Power
Forms of Alternative Energy
Energy Conversions
bull In an automobile engine fuel is burned to convert chemical energy into heat energy The heat energy is then changed into mechanical energy
Chemical Heat Mechanical
The Law of Conservation of Energy
bull Man can neither create nor destroy Energy by ordinary meansoIt can only be converted from one form to another
oIf energy seems to disappear then scientists look for it ndash leading to many important discoveries
Law of Conservation of Energy
bull In 1905 Albert Einstein said that mass and energy can be converted into each other
bull He showed that if matter is destroyed energy is created and if energy is destroyed mass is created
bull E=MC2 bull M=mass C=speed of light
Power = measure of Energybull Work = Force x Distancebull Rate of doing Work orbull Amount of Workunit of timebull Power= WorkTime
bull Power = (Force x Distance)Time
bull Power Units = Watts bull 1Watt=1Joulesec or (1Nmsec)bull 1 Kilowatt = 1000 wattsbull 1 Horsepower = 746 watts
Thermal Energy (Heat) differs from
Temperature
Heat vs Temperaturebull Heat content is the TOTAL
KINETIC ENERGY of the particles in a sample
bull Temperature is the AVERAGE KINETIC ENERGY of the particles in a sample
Which has more Heat and which has the highest temperature
Insulatorsbull There are
thousands of air bubbles trapped in the styrofoam which slows down the heat flow through the layer
Insulation How do the Polar Bears stay warm in
the snow Their dense fine fir traps an air layer next to
their skin
Home Insulationbull The pink fiberglass
fibers trap air in the mat of insulation preventing heat from escaping in the winter or heat from entering during the summer Insulation
Highly Insulating Windows
bull Two or three panes between inside and outside air
bull Insulation is supplied by the Dead Air Space
Image source Southwall Technologies
Heat Transferbull Occurs three waysoConductionoConvectionoRadiation
bull The transfer of heat by direct contact between objects or particles
bull Motion of solid atoms or molecules carried from particle to particle
bull Heat transferred by the movement of molecules within liquid or gaseous substance
bull Warm rises cool sinks
bull A circular motion begins from warmer areas rising due to decreased density moving toward cooler areas which fall because of increased density
bull Wind and Major Weather patterns are caused and move largely because of these convection currents
bull Heat transferred through space
bull MATTER is not needed for radiation
bull EXAMPLE The sunrsquos rays carrying visible light and UV light causing sunburn
Radiationbull Transfer of heat through
electromagnetic radiation (light from stars or light bulbs)
bull Transferred in all directionsbull Matter is not requiredbull Dark or dull objects absorb
more than light or shiny objects do
Temperature
bull Temperature is a measure of the average KE of the particles in a sample of matter
Temperature Conversions
bull oC to oF oF = (95)oC + 32
bull oF to oC oC = 59(oF ndash 32)
bull oC to K K = oC + 273bull K to oC oC = K ndash 273
Going from Celsius to Fahrenheit
Convert 37 oC to oFoF = (95)oC + 32oF = (95)37oC + 32 = 666 + 32 = 986oF
Going from Fahrenheit to CelsiusConvert 68oF to oC
oC = 59(oF ndash 32)oC = 59(68 ndash 32)
= 59(36)
= 20 oC
Going from Kelvin to CelsiusConvert 310 K to oC
oC = K ndash 273oC = 310 ndash 273
= 37oC
Thermal Energybull Which beaker of water has more thermal
energyo B - same temperature but more mass
200 mL
80ordmC
A400 mL
80ordmC
B
Thermal energy relationships a As temperature increases so does
thermal energy (because the kinetic energy of the particles increased)
b Even if the temperature doesnrsquot change the thermal energy in a more massive substance is higher (because it is a total
measure of energy)
c Energy always travels from a high concentration(warm) to a lower concentration(cool) of heat
Land heats up and cools down faster than water The temperature of the water helps keep the
land temperature stable
Thermal Expansionbull Additional heat content causes matter to expandbull Loss of heat content causes matter to contractbull Faster particles take up more space
Sample Problem Thermal Expansion
bull What will be the new volume of 200ml of 20degC water if the temperature is raised to 90degC
bull ∆V = 3σ ∆T Vo
bull = 3 x 69e-6degC x 70degC x 200ml
bull = 2898ml
bull Vnew = Vold + ∆V
bull Vnew = 200ml + 2898ml = 202898ml
Specific heat(CH2O) is the amount of heat required to raise the temperature of 1 kg of a material by one degree (Cdeg or K)
1) C(H2O) = 4184 J kg Cdeg
= 418 kJ kg Cdeg
2) C(sand) = 664 J kg CdegThis is why land heats up quickly during the day and
cools quickly at night and why water takes longer
How to calculate changes in thermal energy
Q = m x Cp x T
Q = quantity of thermal energy
m = mass of substance
T = change in temperature (Tf ndash Ti)
Cp = specific heat of substance(p)
Heat TransferHow much heat is required to warm
230 g of water from 12degC to 90degC
GIVENm = 230 gTi = 12degC
Tf = 90degC
Q = C(H2O)= 4184 JgmiddotoC
WORKQ = mmiddotTmiddotCp
m = 230 gT = 90degC - 12degC = 78degCQ = (230g)(78˚C)(4184 JgmiddotoC)Q = 75061 J
Calorimeters are used to measure the specific heat of a substance
Professional Kingrsquos Ridge
Laws of Thermodynamics
bull First Law Energy is always conservedo Energy added to a system may do two things
bull Increase the total thermal energy of the systembull Do work on the system
o Example Bicycle Pump puts air into tire(work) and heats the air(thermal)
bull Second Law Heat can travel from cold to hot ONLY if work is done on the systemo Example The compressor in a refrigerator
bull Third Law We will never reach Absolute Zero
Uses of Heatbull Heat Engines
o External Combustion Engines Fuel is burned outside of the engine
bull Steam Engine
Internal Combustiono Internal Combustion Engines Fuel is burned inside of the engine
bull Car engines
o 4 stroke engine Pistons are moving up and downbull Intake moving down intake valve open fuel mixture drawn
inbull Compression moving up both valves closedbull Power moving down both valves closed spark igniting fuelbull Exhaust moving up exhaust valve open waste exits
o Cooling system to keep the temperature of the engine within a specific range to prevent damage
o Electrical system Battery is used to start the engine then alternator is used to produce the electricity needed to run the engine and all other systems such as air conditioning
Heating Systemsbull Hot-Water Systemsmdashboilers and radiators -full of hot waterbull Steam Heat Systems-- ldquo -full of hot steambull Electric Heat Systemsmdashproducing heat(lightbulb)bull Forced Air Heating Systemsmdashmost homes todaym burning a fuel
and blowing the warmed air aroundbull Solar Heating using sunlight to heat water and homes
o Passivemdashallowing sunlight to enter home most efficiently and trapping it
o Activemdashcollecting solar energy then heating the home with the energy
bull Heat Pumps evaporators condensers amp coolanto Home Heatingmdashdrawing heat from the warm eartho Refrigeratormdashdrawing heat from the warm food and warm airo Air Conditionermdashdrawing heat from the warm room
States of Energy Kinetic and Potential Energy
bull Kinetic Energy is the energy of motion
bull Potential Energy is stored energy of position or chemical bonds
Nature of Energybull Energy is
involved wheno a bird flieso a bomb
explodeso rain falls from
the skyo electricity
flows in a wire
Kinetic Energybull The energy of motion is called
kinetic energybull The faster an object moves the
more kinetic energy it hasbull The greater the mass of a moving
object the more kinetic energy it has
bull Kinetic energy depends on both mass and velocity
Kinetic Energy
KE = frac12 mass x velocity2
What has a greater affect of kinetic energy mass or velocity Why
Potential Energybull Potential Energy is stored
energyoStored chemically in bonds of fuel
or food oStored as nuclear energy holding
subatomic particles together oOr stored because of the work done
on itbull Stretching a rubber bandbull Winding a watchbull Pulling an arrow back on a bowrsquos string
bull Lifting a brick high in the air
Gravitational Potential Energy
bull Potential energy dependent on height is called Gravitational Potential Energy (a form of mechanical energy)
Gravitational Potential Energy
bull If you stand on a 3-meter diving board you have 3 times the GPE than you had on a 1-meter diving board
bull GPE=Weight x Height
bull (pounds) x (feet)bull or (Newtons) x (meters)
bull GPE = (M)(Ag) (H)bull M=Kg Ag =98msec2H=m
Kinetic ndash Potential Energy Conversion
Cars are mechanically pulled to the peak which is the point of maximum potential energy the car has minimum kinetic energy As position is exchanged for speed potential is converted to kinetic energy
Ball slows down
Ball speeds up
Forms of Energy
bull The five main forms of energy areoHeatoChemicaloElectromagneticoNuclearoMechanical
Heat Energybull The internal motion of the
atoms is called heat energy because moving particles produce heat
bull Heat energy can be produced by friction
bull Heat energy causes changes in temperature and phase of any form of matter
Chemical Energy
bull Chemical Energy is required to bond atoms together
bull And when bonds are broken energy can be released or absorbed
bull Exothermic = energy released
bull Endothermic=energy absorbed
Chemical Energy
bull Fossil Fuels and our Food are forms of energy stored in chemical bondsbull The Energy came from nuclear
fusion on our Sun and was photosynthesized by plants and stored in plant and animal life
Formation of Fossil Fuels
bull Petroleum and Natural gas are both products of millions of years of decomposing Marine life both animal and plant
bull Coal is similar but mostly from terrestrial plant life
Where does Coal come from
Electromagnetic Energybull Electricity -- carried in
wiresbull Light -- Each of the colors
of light (ROY G BIV) represents a different amount of electromagnetic energy
bull X-rays amp Cosmic Raysbull TV amp Radio wavesbull Laser light
Nuclear Energybull When the nucleus
splits (Fission) nuclear energy is released in the form of heat energy and light energy
bull Nuclear energy is also released when nuclei collide at high speeds and join (Fusion)
bull MOST CONCENTRATED
Mechanical Energy
bull When work is done to an object it acquires energy The energy it acquires is known as mechanical energy
Mechanical Energy
bull When you kick a football you give mechanical energy to the football to make it move
Energy Conversionbull Energy can be changed from one form to another Changes in the form of energy are called energy conversions
bull Good Examples on Pages 418-419
Energy conversionsbull All forms of energy can be
converted into other formsoThe sunrsquos energy through solar
cells can be converted directly into electricity(Photovoltaic energy)
oGreen plants convert the sunrsquos energy (electromagnetic) into the bonds in starches and sugars (chemical energy) using Photosynthesis
Other energy conversions
oIn an electric motor electromagnetic energy is converted to mechanical energy
oIn a battery chemical energy is converted into electromagnetic energy
oMechanical energy of water falling can be converted to electrical energy in a generator
Hydroelectric Power
Forms of Alternative Energy
Energy Conversions
bull In an automobile engine fuel is burned to convert chemical energy into heat energy The heat energy is then changed into mechanical energy
Chemical Heat Mechanical
The Law of Conservation of Energy
bull Man can neither create nor destroy Energy by ordinary meansoIt can only be converted from one form to another
oIf energy seems to disappear then scientists look for it ndash leading to many important discoveries
Law of Conservation of Energy
bull In 1905 Albert Einstein said that mass and energy can be converted into each other
bull He showed that if matter is destroyed energy is created and if energy is destroyed mass is created
bull E=MC2 bull M=mass C=speed of light
Power = measure of Energybull Work = Force x Distancebull Rate of doing Work orbull Amount of Workunit of timebull Power= WorkTime
bull Power = (Force x Distance)Time
bull Power Units = Watts bull 1Watt=1Joulesec or (1Nmsec)bull 1 Kilowatt = 1000 wattsbull 1 Horsepower = 746 watts
Thermal Energy (Heat) differs from
Temperature
Heat vs Temperaturebull Heat content is the TOTAL
KINETIC ENERGY of the particles in a sample
bull Temperature is the AVERAGE KINETIC ENERGY of the particles in a sample
Which has more Heat and which has the highest temperature
Insulatorsbull There are
thousands of air bubbles trapped in the styrofoam which slows down the heat flow through the layer
Insulation How do the Polar Bears stay warm in
the snow Their dense fine fir traps an air layer next to
their skin
Home Insulationbull The pink fiberglass
fibers trap air in the mat of insulation preventing heat from escaping in the winter or heat from entering during the summer Insulation
Highly Insulating Windows
bull Two or three panes between inside and outside air
bull Insulation is supplied by the Dead Air Space
Image source Southwall Technologies
Heat Transferbull Occurs three waysoConductionoConvectionoRadiation
bull The transfer of heat by direct contact between objects or particles
bull Motion of solid atoms or molecules carried from particle to particle
bull Heat transferred by the movement of molecules within liquid or gaseous substance
bull Warm rises cool sinks
bull A circular motion begins from warmer areas rising due to decreased density moving toward cooler areas which fall because of increased density
bull Wind and Major Weather patterns are caused and move largely because of these convection currents
bull Heat transferred through space
bull MATTER is not needed for radiation
bull EXAMPLE The sunrsquos rays carrying visible light and UV light causing sunburn
Radiationbull Transfer of heat through
electromagnetic radiation (light from stars or light bulbs)
bull Transferred in all directionsbull Matter is not requiredbull Dark or dull objects absorb
more than light or shiny objects do
Temperature
bull Temperature is a measure of the average KE of the particles in a sample of matter
Temperature Conversions
bull oC to oF oF = (95)oC + 32
bull oF to oC oC = 59(oF ndash 32)
bull oC to K K = oC + 273bull K to oC oC = K ndash 273
Going from Celsius to Fahrenheit
Convert 37 oC to oFoF = (95)oC + 32oF = (95)37oC + 32 = 666 + 32 = 986oF
Going from Fahrenheit to CelsiusConvert 68oF to oC
oC = 59(oF ndash 32)oC = 59(68 ndash 32)
= 59(36)
= 20 oC
Going from Kelvin to CelsiusConvert 310 K to oC
oC = K ndash 273oC = 310 ndash 273
= 37oC
Thermal Energybull Which beaker of water has more thermal
energyo B - same temperature but more mass
200 mL
80ordmC
A400 mL
80ordmC
B
Thermal energy relationships a As temperature increases so does
thermal energy (because the kinetic energy of the particles increased)
b Even if the temperature doesnrsquot change the thermal energy in a more massive substance is higher (because it is a total
measure of energy)
c Energy always travels from a high concentration(warm) to a lower concentration(cool) of heat
Land heats up and cools down faster than water The temperature of the water helps keep the
land temperature stable
Thermal Expansionbull Additional heat content causes matter to expandbull Loss of heat content causes matter to contractbull Faster particles take up more space
Sample Problem Thermal Expansion
bull What will be the new volume of 200ml of 20degC water if the temperature is raised to 90degC
bull ∆V = 3σ ∆T Vo
bull = 3 x 69e-6degC x 70degC x 200ml
bull = 2898ml
bull Vnew = Vold + ∆V
bull Vnew = 200ml + 2898ml = 202898ml
Specific heat(CH2O) is the amount of heat required to raise the temperature of 1 kg of a material by one degree (Cdeg or K)
1) C(H2O) = 4184 J kg Cdeg
= 418 kJ kg Cdeg
2) C(sand) = 664 J kg CdegThis is why land heats up quickly during the day and
cools quickly at night and why water takes longer
How to calculate changes in thermal energy
Q = m x Cp x T
Q = quantity of thermal energy
m = mass of substance
T = change in temperature (Tf ndash Ti)
Cp = specific heat of substance(p)
Heat TransferHow much heat is required to warm
230 g of water from 12degC to 90degC
GIVENm = 230 gTi = 12degC
Tf = 90degC
Q = C(H2O)= 4184 JgmiddotoC
WORKQ = mmiddotTmiddotCp
m = 230 gT = 90degC - 12degC = 78degCQ = (230g)(78˚C)(4184 JgmiddotoC)Q = 75061 J
Calorimeters are used to measure the specific heat of a substance
Professional Kingrsquos Ridge
Laws of Thermodynamics
bull First Law Energy is always conservedo Energy added to a system may do two things
bull Increase the total thermal energy of the systembull Do work on the system
o Example Bicycle Pump puts air into tire(work) and heats the air(thermal)
bull Second Law Heat can travel from cold to hot ONLY if work is done on the systemo Example The compressor in a refrigerator
bull Third Law We will never reach Absolute Zero
Uses of Heatbull Heat Engines
o External Combustion Engines Fuel is burned outside of the engine
bull Steam Engine
Internal Combustiono Internal Combustion Engines Fuel is burned inside of the engine
bull Car engines
o 4 stroke engine Pistons are moving up and downbull Intake moving down intake valve open fuel mixture drawn
inbull Compression moving up both valves closedbull Power moving down both valves closed spark igniting fuelbull Exhaust moving up exhaust valve open waste exits
o Cooling system to keep the temperature of the engine within a specific range to prevent damage
o Electrical system Battery is used to start the engine then alternator is used to produce the electricity needed to run the engine and all other systems such as air conditioning
Heating Systemsbull Hot-Water Systemsmdashboilers and radiators -full of hot waterbull Steam Heat Systems-- ldquo -full of hot steambull Electric Heat Systemsmdashproducing heat(lightbulb)bull Forced Air Heating Systemsmdashmost homes todaym burning a fuel
and blowing the warmed air aroundbull Solar Heating using sunlight to heat water and homes
o Passivemdashallowing sunlight to enter home most efficiently and trapping it
o Activemdashcollecting solar energy then heating the home with the energy
bull Heat Pumps evaporators condensers amp coolanto Home Heatingmdashdrawing heat from the warm eartho Refrigeratormdashdrawing heat from the warm food and warm airo Air Conditionermdashdrawing heat from the warm room
Nature of Energybull Energy is
involved wheno a bird flieso a bomb
explodeso rain falls from
the skyo electricity
flows in a wire
Kinetic Energybull The energy of motion is called
kinetic energybull The faster an object moves the
more kinetic energy it hasbull The greater the mass of a moving
object the more kinetic energy it has
bull Kinetic energy depends on both mass and velocity
Kinetic Energy
KE = frac12 mass x velocity2
What has a greater affect of kinetic energy mass or velocity Why
Potential Energybull Potential Energy is stored
energyoStored chemically in bonds of fuel
or food oStored as nuclear energy holding
subatomic particles together oOr stored because of the work done
on itbull Stretching a rubber bandbull Winding a watchbull Pulling an arrow back on a bowrsquos string
bull Lifting a brick high in the air
Gravitational Potential Energy
bull Potential energy dependent on height is called Gravitational Potential Energy (a form of mechanical energy)
Gravitational Potential Energy
bull If you stand on a 3-meter diving board you have 3 times the GPE than you had on a 1-meter diving board
bull GPE=Weight x Height
bull (pounds) x (feet)bull or (Newtons) x (meters)
bull GPE = (M)(Ag) (H)bull M=Kg Ag =98msec2H=m
Kinetic ndash Potential Energy Conversion
Cars are mechanically pulled to the peak which is the point of maximum potential energy the car has minimum kinetic energy As position is exchanged for speed potential is converted to kinetic energy
Ball slows down
Ball speeds up
Forms of Energy
bull The five main forms of energy areoHeatoChemicaloElectromagneticoNuclearoMechanical
Heat Energybull The internal motion of the
atoms is called heat energy because moving particles produce heat
bull Heat energy can be produced by friction
bull Heat energy causes changes in temperature and phase of any form of matter
Chemical Energy
bull Chemical Energy is required to bond atoms together
bull And when bonds are broken energy can be released or absorbed
bull Exothermic = energy released
bull Endothermic=energy absorbed
Chemical Energy
bull Fossil Fuels and our Food are forms of energy stored in chemical bondsbull The Energy came from nuclear
fusion on our Sun and was photosynthesized by plants and stored in plant and animal life
Formation of Fossil Fuels
bull Petroleum and Natural gas are both products of millions of years of decomposing Marine life both animal and plant
bull Coal is similar but mostly from terrestrial plant life
Where does Coal come from
Electromagnetic Energybull Electricity -- carried in
wiresbull Light -- Each of the colors
of light (ROY G BIV) represents a different amount of electromagnetic energy
bull X-rays amp Cosmic Raysbull TV amp Radio wavesbull Laser light
Nuclear Energybull When the nucleus
splits (Fission) nuclear energy is released in the form of heat energy and light energy
bull Nuclear energy is also released when nuclei collide at high speeds and join (Fusion)
bull MOST CONCENTRATED
Mechanical Energy
bull When work is done to an object it acquires energy The energy it acquires is known as mechanical energy
Mechanical Energy
bull When you kick a football you give mechanical energy to the football to make it move
Energy Conversionbull Energy can be changed from one form to another Changes in the form of energy are called energy conversions
bull Good Examples on Pages 418-419
Energy conversionsbull All forms of energy can be
converted into other formsoThe sunrsquos energy through solar
cells can be converted directly into electricity(Photovoltaic energy)
oGreen plants convert the sunrsquos energy (electromagnetic) into the bonds in starches and sugars (chemical energy) using Photosynthesis
Other energy conversions
oIn an electric motor electromagnetic energy is converted to mechanical energy
oIn a battery chemical energy is converted into electromagnetic energy
oMechanical energy of water falling can be converted to electrical energy in a generator
Hydroelectric Power
Forms of Alternative Energy
Energy Conversions
bull In an automobile engine fuel is burned to convert chemical energy into heat energy The heat energy is then changed into mechanical energy
Chemical Heat Mechanical
The Law of Conservation of Energy
bull Man can neither create nor destroy Energy by ordinary meansoIt can only be converted from one form to another
oIf energy seems to disappear then scientists look for it ndash leading to many important discoveries
Law of Conservation of Energy
bull In 1905 Albert Einstein said that mass and energy can be converted into each other
bull He showed that if matter is destroyed energy is created and if energy is destroyed mass is created
bull E=MC2 bull M=mass C=speed of light
Power = measure of Energybull Work = Force x Distancebull Rate of doing Work orbull Amount of Workunit of timebull Power= WorkTime
bull Power = (Force x Distance)Time
bull Power Units = Watts bull 1Watt=1Joulesec or (1Nmsec)bull 1 Kilowatt = 1000 wattsbull 1 Horsepower = 746 watts
Thermal Energy (Heat) differs from
Temperature
Heat vs Temperaturebull Heat content is the TOTAL
KINETIC ENERGY of the particles in a sample
bull Temperature is the AVERAGE KINETIC ENERGY of the particles in a sample
Which has more Heat and which has the highest temperature
Insulatorsbull There are
thousands of air bubbles trapped in the styrofoam which slows down the heat flow through the layer
Insulation How do the Polar Bears stay warm in
the snow Their dense fine fir traps an air layer next to
their skin
Home Insulationbull The pink fiberglass
fibers trap air in the mat of insulation preventing heat from escaping in the winter or heat from entering during the summer Insulation
Highly Insulating Windows
bull Two or three panes between inside and outside air
bull Insulation is supplied by the Dead Air Space
Image source Southwall Technologies
Heat Transferbull Occurs three waysoConductionoConvectionoRadiation
bull The transfer of heat by direct contact between objects or particles
bull Motion of solid atoms or molecules carried from particle to particle
bull Heat transferred by the movement of molecules within liquid or gaseous substance
bull Warm rises cool sinks
bull A circular motion begins from warmer areas rising due to decreased density moving toward cooler areas which fall because of increased density
bull Wind and Major Weather patterns are caused and move largely because of these convection currents
bull Heat transferred through space
bull MATTER is not needed for radiation
bull EXAMPLE The sunrsquos rays carrying visible light and UV light causing sunburn
Radiationbull Transfer of heat through
electromagnetic radiation (light from stars or light bulbs)
bull Transferred in all directionsbull Matter is not requiredbull Dark or dull objects absorb
more than light or shiny objects do
Temperature
bull Temperature is a measure of the average KE of the particles in a sample of matter
Temperature Conversions
bull oC to oF oF = (95)oC + 32
bull oF to oC oC = 59(oF ndash 32)
bull oC to K K = oC + 273bull K to oC oC = K ndash 273
Going from Celsius to Fahrenheit
Convert 37 oC to oFoF = (95)oC + 32oF = (95)37oC + 32 = 666 + 32 = 986oF
Going from Fahrenheit to CelsiusConvert 68oF to oC
oC = 59(oF ndash 32)oC = 59(68 ndash 32)
= 59(36)
= 20 oC
Going from Kelvin to CelsiusConvert 310 K to oC
oC = K ndash 273oC = 310 ndash 273
= 37oC
Thermal Energybull Which beaker of water has more thermal
energyo B - same temperature but more mass
200 mL
80ordmC
A400 mL
80ordmC
B
Thermal energy relationships a As temperature increases so does
thermal energy (because the kinetic energy of the particles increased)
b Even if the temperature doesnrsquot change the thermal energy in a more massive substance is higher (because it is a total
measure of energy)
c Energy always travels from a high concentration(warm) to a lower concentration(cool) of heat
Land heats up and cools down faster than water The temperature of the water helps keep the
land temperature stable
Thermal Expansionbull Additional heat content causes matter to expandbull Loss of heat content causes matter to contractbull Faster particles take up more space
Sample Problem Thermal Expansion
bull What will be the new volume of 200ml of 20degC water if the temperature is raised to 90degC
bull ∆V = 3σ ∆T Vo
bull = 3 x 69e-6degC x 70degC x 200ml
bull = 2898ml
bull Vnew = Vold + ∆V
bull Vnew = 200ml + 2898ml = 202898ml
Specific heat(CH2O) is the amount of heat required to raise the temperature of 1 kg of a material by one degree (Cdeg or K)
1) C(H2O) = 4184 J kg Cdeg
= 418 kJ kg Cdeg
2) C(sand) = 664 J kg CdegThis is why land heats up quickly during the day and
cools quickly at night and why water takes longer
How to calculate changes in thermal energy
Q = m x Cp x T
Q = quantity of thermal energy
m = mass of substance
T = change in temperature (Tf ndash Ti)
Cp = specific heat of substance(p)
Heat TransferHow much heat is required to warm
230 g of water from 12degC to 90degC
GIVENm = 230 gTi = 12degC
Tf = 90degC
Q = C(H2O)= 4184 JgmiddotoC
WORKQ = mmiddotTmiddotCp
m = 230 gT = 90degC - 12degC = 78degCQ = (230g)(78˚C)(4184 JgmiddotoC)Q = 75061 J
Calorimeters are used to measure the specific heat of a substance
Professional Kingrsquos Ridge
Laws of Thermodynamics
bull First Law Energy is always conservedo Energy added to a system may do two things
bull Increase the total thermal energy of the systembull Do work on the system
o Example Bicycle Pump puts air into tire(work) and heats the air(thermal)
bull Second Law Heat can travel from cold to hot ONLY if work is done on the systemo Example The compressor in a refrigerator
bull Third Law We will never reach Absolute Zero
Uses of Heatbull Heat Engines
o External Combustion Engines Fuel is burned outside of the engine
bull Steam Engine
Internal Combustiono Internal Combustion Engines Fuel is burned inside of the engine
bull Car engines
o 4 stroke engine Pistons are moving up and downbull Intake moving down intake valve open fuel mixture drawn
inbull Compression moving up both valves closedbull Power moving down both valves closed spark igniting fuelbull Exhaust moving up exhaust valve open waste exits
o Cooling system to keep the temperature of the engine within a specific range to prevent damage
o Electrical system Battery is used to start the engine then alternator is used to produce the electricity needed to run the engine and all other systems such as air conditioning
Heating Systemsbull Hot-Water Systemsmdashboilers and radiators -full of hot waterbull Steam Heat Systems-- ldquo -full of hot steambull Electric Heat Systemsmdashproducing heat(lightbulb)bull Forced Air Heating Systemsmdashmost homes todaym burning a fuel
and blowing the warmed air aroundbull Solar Heating using sunlight to heat water and homes
o Passivemdashallowing sunlight to enter home most efficiently and trapping it
o Activemdashcollecting solar energy then heating the home with the energy
bull Heat Pumps evaporators condensers amp coolanto Home Heatingmdashdrawing heat from the warm eartho Refrigeratormdashdrawing heat from the warm food and warm airo Air Conditionermdashdrawing heat from the warm room
Kinetic Energybull The energy of motion is called
kinetic energybull The faster an object moves the
more kinetic energy it hasbull The greater the mass of a moving
object the more kinetic energy it has
bull Kinetic energy depends on both mass and velocity
Kinetic Energy
KE = frac12 mass x velocity2
What has a greater affect of kinetic energy mass or velocity Why
Potential Energybull Potential Energy is stored
energyoStored chemically in bonds of fuel
or food oStored as nuclear energy holding
subatomic particles together oOr stored because of the work done
on itbull Stretching a rubber bandbull Winding a watchbull Pulling an arrow back on a bowrsquos string
bull Lifting a brick high in the air
Gravitational Potential Energy
bull Potential energy dependent on height is called Gravitational Potential Energy (a form of mechanical energy)
Gravitational Potential Energy
bull If you stand on a 3-meter diving board you have 3 times the GPE than you had on a 1-meter diving board
bull GPE=Weight x Height
bull (pounds) x (feet)bull or (Newtons) x (meters)
bull GPE = (M)(Ag) (H)bull M=Kg Ag =98msec2H=m
Kinetic ndash Potential Energy Conversion
Cars are mechanically pulled to the peak which is the point of maximum potential energy the car has minimum kinetic energy As position is exchanged for speed potential is converted to kinetic energy
Ball slows down
Ball speeds up
Forms of Energy
bull The five main forms of energy areoHeatoChemicaloElectromagneticoNuclearoMechanical
Heat Energybull The internal motion of the
atoms is called heat energy because moving particles produce heat
bull Heat energy can be produced by friction
bull Heat energy causes changes in temperature and phase of any form of matter
Chemical Energy
bull Chemical Energy is required to bond atoms together
bull And when bonds are broken energy can be released or absorbed
bull Exothermic = energy released
bull Endothermic=energy absorbed
Chemical Energy
bull Fossil Fuels and our Food are forms of energy stored in chemical bondsbull The Energy came from nuclear
fusion on our Sun and was photosynthesized by plants and stored in plant and animal life
Formation of Fossil Fuels
bull Petroleum and Natural gas are both products of millions of years of decomposing Marine life both animal and plant
bull Coal is similar but mostly from terrestrial plant life
Where does Coal come from
Electromagnetic Energybull Electricity -- carried in
wiresbull Light -- Each of the colors
of light (ROY G BIV) represents a different amount of electromagnetic energy
bull X-rays amp Cosmic Raysbull TV amp Radio wavesbull Laser light
Nuclear Energybull When the nucleus
splits (Fission) nuclear energy is released in the form of heat energy and light energy
bull Nuclear energy is also released when nuclei collide at high speeds and join (Fusion)
bull MOST CONCENTRATED
Mechanical Energy
bull When work is done to an object it acquires energy The energy it acquires is known as mechanical energy
Mechanical Energy
bull When you kick a football you give mechanical energy to the football to make it move
Energy Conversionbull Energy can be changed from one form to another Changes in the form of energy are called energy conversions
bull Good Examples on Pages 418-419
Energy conversionsbull All forms of energy can be
converted into other formsoThe sunrsquos energy through solar
cells can be converted directly into electricity(Photovoltaic energy)
oGreen plants convert the sunrsquos energy (electromagnetic) into the bonds in starches and sugars (chemical energy) using Photosynthesis
Other energy conversions
oIn an electric motor electromagnetic energy is converted to mechanical energy
oIn a battery chemical energy is converted into electromagnetic energy
oMechanical energy of water falling can be converted to electrical energy in a generator
Hydroelectric Power
Forms of Alternative Energy
Energy Conversions
bull In an automobile engine fuel is burned to convert chemical energy into heat energy The heat energy is then changed into mechanical energy
Chemical Heat Mechanical
The Law of Conservation of Energy
bull Man can neither create nor destroy Energy by ordinary meansoIt can only be converted from one form to another
oIf energy seems to disappear then scientists look for it ndash leading to many important discoveries
Law of Conservation of Energy
bull In 1905 Albert Einstein said that mass and energy can be converted into each other
bull He showed that if matter is destroyed energy is created and if energy is destroyed mass is created
bull E=MC2 bull M=mass C=speed of light
Power = measure of Energybull Work = Force x Distancebull Rate of doing Work orbull Amount of Workunit of timebull Power= WorkTime
bull Power = (Force x Distance)Time
bull Power Units = Watts bull 1Watt=1Joulesec or (1Nmsec)bull 1 Kilowatt = 1000 wattsbull 1 Horsepower = 746 watts
Thermal Energy (Heat) differs from
Temperature
Heat vs Temperaturebull Heat content is the TOTAL
KINETIC ENERGY of the particles in a sample
bull Temperature is the AVERAGE KINETIC ENERGY of the particles in a sample
Which has more Heat and which has the highest temperature
Insulatorsbull There are
thousands of air bubbles trapped in the styrofoam which slows down the heat flow through the layer
Insulation How do the Polar Bears stay warm in
the snow Their dense fine fir traps an air layer next to
their skin
Home Insulationbull The pink fiberglass
fibers trap air in the mat of insulation preventing heat from escaping in the winter or heat from entering during the summer Insulation
Highly Insulating Windows
bull Two or three panes between inside and outside air
bull Insulation is supplied by the Dead Air Space
Image source Southwall Technologies
Heat Transferbull Occurs three waysoConductionoConvectionoRadiation
bull The transfer of heat by direct contact between objects or particles
bull Motion of solid atoms or molecules carried from particle to particle
bull Heat transferred by the movement of molecules within liquid or gaseous substance
bull Warm rises cool sinks
bull A circular motion begins from warmer areas rising due to decreased density moving toward cooler areas which fall because of increased density
bull Wind and Major Weather patterns are caused and move largely because of these convection currents
bull Heat transferred through space
bull MATTER is not needed for radiation
bull EXAMPLE The sunrsquos rays carrying visible light and UV light causing sunburn
Radiationbull Transfer of heat through
electromagnetic radiation (light from stars or light bulbs)
bull Transferred in all directionsbull Matter is not requiredbull Dark or dull objects absorb
more than light or shiny objects do
Temperature
bull Temperature is a measure of the average KE of the particles in a sample of matter
Temperature Conversions
bull oC to oF oF = (95)oC + 32
bull oF to oC oC = 59(oF ndash 32)
bull oC to K K = oC + 273bull K to oC oC = K ndash 273
Going from Celsius to Fahrenheit
Convert 37 oC to oFoF = (95)oC + 32oF = (95)37oC + 32 = 666 + 32 = 986oF
Going from Fahrenheit to CelsiusConvert 68oF to oC
oC = 59(oF ndash 32)oC = 59(68 ndash 32)
= 59(36)
= 20 oC
Going from Kelvin to CelsiusConvert 310 K to oC
oC = K ndash 273oC = 310 ndash 273
= 37oC
Thermal Energybull Which beaker of water has more thermal
energyo B - same temperature but more mass
200 mL
80ordmC
A400 mL
80ordmC
B
Thermal energy relationships a As temperature increases so does
thermal energy (because the kinetic energy of the particles increased)
b Even if the temperature doesnrsquot change the thermal energy in a more massive substance is higher (because it is a total
measure of energy)
c Energy always travels from a high concentration(warm) to a lower concentration(cool) of heat
Land heats up and cools down faster than water The temperature of the water helps keep the
land temperature stable
Thermal Expansionbull Additional heat content causes matter to expandbull Loss of heat content causes matter to contractbull Faster particles take up more space
Sample Problem Thermal Expansion
bull What will be the new volume of 200ml of 20degC water if the temperature is raised to 90degC
bull ∆V = 3σ ∆T Vo
bull = 3 x 69e-6degC x 70degC x 200ml
bull = 2898ml
bull Vnew = Vold + ∆V
bull Vnew = 200ml + 2898ml = 202898ml
Specific heat(CH2O) is the amount of heat required to raise the temperature of 1 kg of a material by one degree (Cdeg or K)
1) C(H2O) = 4184 J kg Cdeg
= 418 kJ kg Cdeg
2) C(sand) = 664 J kg CdegThis is why land heats up quickly during the day and
cools quickly at night and why water takes longer
How to calculate changes in thermal energy
Q = m x Cp x T
Q = quantity of thermal energy
m = mass of substance
T = change in temperature (Tf ndash Ti)
Cp = specific heat of substance(p)
Heat TransferHow much heat is required to warm
230 g of water from 12degC to 90degC
GIVENm = 230 gTi = 12degC
Tf = 90degC
Q = C(H2O)= 4184 JgmiddotoC
WORKQ = mmiddotTmiddotCp
m = 230 gT = 90degC - 12degC = 78degCQ = (230g)(78˚C)(4184 JgmiddotoC)Q = 75061 J
Calorimeters are used to measure the specific heat of a substance
Professional Kingrsquos Ridge
Laws of Thermodynamics
bull First Law Energy is always conservedo Energy added to a system may do two things
bull Increase the total thermal energy of the systembull Do work on the system
o Example Bicycle Pump puts air into tire(work) and heats the air(thermal)
bull Second Law Heat can travel from cold to hot ONLY if work is done on the systemo Example The compressor in a refrigerator
bull Third Law We will never reach Absolute Zero
Uses of Heatbull Heat Engines
o External Combustion Engines Fuel is burned outside of the engine
bull Steam Engine
Internal Combustiono Internal Combustion Engines Fuel is burned inside of the engine
bull Car engines
o 4 stroke engine Pistons are moving up and downbull Intake moving down intake valve open fuel mixture drawn
inbull Compression moving up both valves closedbull Power moving down both valves closed spark igniting fuelbull Exhaust moving up exhaust valve open waste exits
o Cooling system to keep the temperature of the engine within a specific range to prevent damage
o Electrical system Battery is used to start the engine then alternator is used to produce the electricity needed to run the engine and all other systems such as air conditioning
Heating Systemsbull Hot-Water Systemsmdashboilers and radiators -full of hot waterbull Steam Heat Systems-- ldquo -full of hot steambull Electric Heat Systemsmdashproducing heat(lightbulb)bull Forced Air Heating Systemsmdashmost homes todaym burning a fuel
and blowing the warmed air aroundbull Solar Heating using sunlight to heat water and homes
o Passivemdashallowing sunlight to enter home most efficiently and trapping it
o Activemdashcollecting solar energy then heating the home with the energy
bull Heat Pumps evaporators condensers amp coolanto Home Heatingmdashdrawing heat from the warm eartho Refrigeratormdashdrawing heat from the warm food and warm airo Air Conditionermdashdrawing heat from the warm room
Kinetic Energy
KE = frac12 mass x velocity2
What has a greater affect of kinetic energy mass or velocity Why
Potential Energybull Potential Energy is stored
energyoStored chemically in bonds of fuel
or food oStored as nuclear energy holding
subatomic particles together oOr stored because of the work done
on itbull Stretching a rubber bandbull Winding a watchbull Pulling an arrow back on a bowrsquos string
bull Lifting a brick high in the air
Gravitational Potential Energy
bull Potential energy dependent on height is called Gravitational Potential Energy (a form of mechanical energy)
Gravitational Potential Energy
bull If you stand on a 3-meter diving board you have 3 times the GPE than you had on a 1-meter diving board
bull GPE=Weight x Height
bull (pounds) x (feet)bull or (Newtons) x (meters)
bull GPE = (M)(Ag) (H)bull M=Kg Ag =98msec2H=m
Kinetic ndash Potential Energy Conversion
Cars are mechanically pulled to the peak which is the point of maximum potential energy the car has minimum kinetic energy As position is exchanged for speed potential is converted to kinetic energy
Ball slows down
Ball speeds up
Forms of Energy
bull The five main forms of energy areoHeatoChemicaloElectromagneticoNuclearoMechanical
Heat Energybull The internal motion of the
atoms is called heat energy because moving particles produce heat
bull Heat energy can be produced by friction
bull Heat energy causes changes in temperature and phase of any form of matter
Chemical Energy
bull Chemical Energy is required to bond atoms together
bull And when bonds are broken energy can be released or absorbed
bull Exothermic = energy released
bull Endothermic=energy absorbed
Chemical Energy
bull Fossil Fuels and our Food are forms of energy stored in chemical bondsbull The Energy came from nuclear
fusion on our Sun and was photosynthesized by plants and stored in plant and animal life
Formation of Fossil Fuels
bull Petroleum and Natural gas are both products of millions of years of decomposing Marine life both animal and plant
bull Coal is similar but mostly from terrestrial plant life
Where does Coal come from
Electromagnetic Energybull Electricity -- carried in
wiresbull Light -- Each of the colors
of light (ROY G BIV) represents a different amount of electromagnetic energy
bull X-rays amp Cosmic Raysbull TV amp Radio wavesbull Laser light
Nuclear Energybull When the nucleus
splits (Fission) nuclear energy is released in the form of heat energy and light energy
bull Nuclear energy is also released when nuclei collide at high speeds and join (Fusion)
bull MOST CONCENTRATED
Mechanical Energy
bull When work is done to an object it acquires energy The energy it acquires is known as mechanical energy
Mechanical Energy
bull When you kick a football you give mechanical energy to the football to make it move
Energy Conversionbull Energy can be changed from one form to another Changes in the form of energy are called energy conversions
bull Good Examples on Pages 418-419
Energy conversionsbull All forms of energy can be
converted into other formsoThe sunrsquos energy through solar
cells can be converted directly into electricity(Photovoltaic energy)
oGreen plants convert the sunrsquos energy (electromagnetic) into the bonds in starches and sugars (chemical energy) using Photosynthesis
Other energy conversions
oIn an electric motor electromagnetic energy is converted to mechanical energy
oIn a battery chemical energy is converted into electromagnetic energy
oMechanical energy of water falling can be converted to electrical energy in a generator
Hydroelectric Power
Forms of Alternative Energy
Energy Conversions
bull In an automobile engine fuel is burned to convert chemical energy into heat energy The heat energy is then changed into mechanical energy
Chemical Heat Mechanical
The Law of Conservation of Energy
bull Man can neither create nor destroy Energy by ordinary meansoIt can only be converted from one form to another
oIf energy seems to disappear then scientists look for it ndash leading to many important discoveries
Law of Conservation of Energy
bull In 1905 Albert Einstein said that mass and energy can be converted into each other
bull He showed that if matter is destroyed energy is created and if energy is destroyed mass is created
bull E=MC2 bull M=mass C=speed of light
Power = measure of Energybull Work = Force x Distancebull Rate of doing Work orbull Amount of Workunit of timebull Power= WorkTime
bull Power = (Force x Distance)Time
bull Power Units = Watts bull 1Watt=1Joulesec or (1Nmsec)bull 1 Kilowatt = 1000 wattsbull 1 Horsepower = 746 watts
Thermal Energy (Heat) differs from
Temperature
Heat vs Temperaturebull Heat content is the TOTAL
KINETIC ENERGY of the particles in a sample
bull Temperature is the AVERAGE KINETIC ENERGY of the particles in a sample
Which has more Heat and which has the highest temperature
Insulatorsbull There are
thousands of air bubbles trapped in the styrofoam which slows down the heat flow through the layer
Insulation How do the Polar Bears stay warm in
the snow Their dense fine fir traps an air layer next to
their skin
Home Insulationbull The pink fiberglass
fibers trap air in the mat of insulation preventing heat from escaping in the winter or heat from entering during the summer Insulation
Highly Insulating Windows
bull Two or three panes between inside and outside air
bull Insulation is supplied by the Dead Air Space
Image source Southwall Technologies
Heat Transferbull Occurs three waysoConductionoConvectionoRadiation
bull The transfer of heat by direct contact between objects or particles
bull Motion of solid atoms or molecules carried from particle to particle
bull Heat transferred by the movement of molecules within liquid or gaseous substance
bull Warm rises cool sinks
bull A circular motion begins from warmer areas rising due to decreased density moving toward cooler areas which fall because of increased density
bull Wind and Major Weather patterns are caused and move largely because of these convection currents
bull Heat transferred through space
bull MATTER is not needed for radiation
bull EXAMPLE The sunrsquos rays carrying visible light and UV light causing sunburn
Radiationbull Transfer of heat through
electromagnetic radiation (light from stars or light bulbs)
bull Transferred in all directionsbull Matter is not requiredbull Dark or dull objects absorb
more than light or shiny objects do
Temperature
bull Temperature is a measure of the average KE of the particles in a sample of matter
Temperature Conversions
bull oC to oF oF = (95)oC + 32
bull oF to oC oC = 59(oF ndash 32)
bull oC to K K = oC + 273bull K to oC oC = K ndash 273
Going from Celsius to Fahrenheit
Convert 37 oC to oFoF = (95)oC + 32oF = (95)37oC + 32 = 666 + 32 = 986oF
Going from Fahrenheit to CelsiusConvert 68oF to oC
oC = 59(oF ndash 32)oC = 59(68 ndash 32)
= 59(36)
= 20 oC
Going from Kelvin to CelsiusConvert 310 K to oC
oC = K ndash 273oC = 310 ndash 273
= 37oC
Thermal Energybull Which beaker of water has more thermal
energyo B - same temperature but more mass
200 mL
80ordmC
A400 mL
80ordmC
B
Thermal energy relationships a As temperature increases so does
thermal energy (because the kinetic energy of the particles increased)
b Even if the temperature doesnrsquot change the thermal energy in a more massive substance is higher (because it is a total
measure of energy)
c Energy always travels from a high concentration(warm) to a lower concentration(cool) of heat
Land heats up and cools down faster than water The temperature of the water helps keep the
land temperature stable
Thermal Expansionbull Additional heat content causes matter to expandbull Loss of heat content causes matter to contractbull Faster particles take up more space
Sample Problem Thermal Expansion
bull What will be the new volume of 200ml of 20degC water if the temperature is raised to 90degC
bull ∆V = 3σ ∆T Vo
bull = 3 x 69e-6degC x 70degC x 200ml
bull = 2898ml
bull Vnew = Vold + ∆V
bull Vnew = 200ml + 2898ml = 202898ml
Specific heat(CH2O) is the amount of heat required to raise the temperature of 1 kg of a material by one degree (Cdeg or K)
1) C(H2O) = 4184 J kg Cdeg
= 418 kJ kg Cdeg
2) C(sand) = 664 J kg CdegThis is why land heats up quickly during the day and
cools quickly at night and why water takes longer
How to calculate changes in thermal energy
Q = m x Cp x T
Q = quantity of thermal energy
m = mass of substance
T = change in temperature (Tf ndash Ti)
Cp = specific heat of substance(p)
Heat TransferHow much heat is required to warm
230 g of water from 12degC to 90degC
GIVENm = 230 gTi = 12degC
Tf = 90degC
Q = C(H2O)= 4184 JgmiddotoC
WORKQ = mmiddotTmiddotCp
m = 230 gT = 90degC - 12degC = 78degCQ = (230g)(78˚C)(4184 JgmiddotoC)Q = 75061 J
Calorimeters are used to measure the specific heat of a substance
Professional Kingrsquos Ridge
Laws of Thermodynamics
bull First Law Energy is always conservedo Energy added to a system may do two things
bull Increase the total thermal energy of the systembull Do work on the system
o Example Bicycle Pump puts air into tire(work) and heats the air(thermal)
bull Second Law Heat can travel from cold to hot ONLY if work is done on the systemo Example The compressor in a refrigerator
bull Third Law We will never reach Absolute Zero
Uses of Heatbull Heat Engines
o External Combustion Engines Fuel is burned outside of the engine
bull Steam Engine
Internal Combustiono Internal Combustion Engines Fuel is burned inside of the engine
bull Car engines
o 4 stroke engine Pistons are moving up and downbull Intake moving down intake valve open fuel mixture drawn
inbull Compression moving up both valves closedbull Power moving down both valves closed spark igniting fuelbull Exhaust moving up exhaust valve open waste exits
o Cooling system to keep the temperature of the engine within a specific range to prevent damage
o Electrical system Battery is used to start the engine then alternator is used to produce the electricity needed to run the engine and all other systems such as air conditioning
Heating Systemsbull Hot-Water Systemsmdashboilers and radiators -full of hot waterbull Steam Heat Systems-- ldquo -full of hot steambull Electric Heat Systemsmdashproducing heat(lightbulb)bull Forced Air Heating Systemsmdashmost homes todaym burning a fuel
and blowing the warmed air aroundbull Solar Heating using sunlight to heat water and homes
o Passivemdashallowing sunlight to enter home most efficiently and trapping it
o Activemdashcollecting solar energy then heating the home with the energy
bull Heat Pumps evaporators condensers amp coolanto Home Heatingmdashdrawing heat from the warm eartho Refrigeratormdashdrawing heat from the warm food and warm airo Air Conditionermdashdrawing heat from the warm room
Potential Energybull Potential Energy is stored
energyoStored chemically in bonds of fuel
or food oStored as nuclear energy holding
subatomic particles together oOr stored because of the work done
on itbull Stretching a rubber bandbull Winding a watchbull Pulling an arrow back on a bowrsquos string
bull Lifting a brick high in the air
Gravitational Potential Energy
bull Potential energy dependent on height is called Gravitational Potential Energy (a form of mechanical energy)
Gravitational Potential Energy
bull If you stand on a 3-meter diving board you have 3 times the GPE than you had on a 1-meter diving board
bull GPE=Weight x Height
bull (pounds) x (feet)bull or (Newtons) x (meters)
bull GPE = (M)(Ag) (H)bull M=Kg Ag =98msec2H=m
Kinetic ndash Potential Energy Conversion
Cars are mechanically pulled to the peak which is the point of maximum potential energy the car has minimum kinetic energy As position is exchanged for speed potential is converted to kinetic energy
Ball slows down
Ball speeds up
Forms of Energy
bull The five main forms of energy areoHeatoChemicaloElectromagneticoNuclearoMechanical
Heat Energybull The internal motion of the
atoms is called heat energy because moving particles produce heat
bull Heat energy can be produced by friction
bull Heat energy causes changes in temperature and phase of any form of matter
Chemical Energy
bull Chemical Energy is required to bond atoms together
bull And when bonds are broken energy can be released or absorbed
bull Exothermic = energy released
bull Endothermic=energy absorbed
Chemical Energy
bull Fossil Fuels and our Food are forms of energy stored in chemical bondsbull The Energy came from nuclear
fusion on our Sun and was photosynthesized by plants and stored in plant and animal life
Formation of Fossil Fuels
bull Petroleum and Natural gas are both products of millions of years of decomposing Marine life both animal and plant
bull Coal is similar but mostly from terrestrial plant life
Where does Coal come from
Electromagnetic Energybull Electricity -- carried in
wiresbull Light -- Each of the colors
of light (ROY G BIV) represents a different amount of electromagnetic energy
bull X-rays amp Cosmic Raysbull TV amp Radio wavesbull Laser light
Nuclear Energybull When the nucleus
splits (Fission) nuclear energy is released in the form of heat energy and light energy
bull Nuclear energy is also released when nuclei collide at high speeds and join (Fusion)
bull MOST CONCENTRATED
Mechanical Energy
bull When work is done to an object it acquires energy The energy it acquires is known as mechanical energy
Mechanical Energy
bull When you kick a football you give mechanical energy to the football to make it move
Energy Conversionbull Energy can be changed from one form to another Changes in the form of energy are called energy conversions
bull Good Examples on Pages 418-419
Energy conversionsbull All forms of energy can be
converted into other formsoThe sunrsquos energy through solar
cells can be converted directly into electricity(Photovoltaic energy)
oGreen plants convert the sunrsquos energy (electromagnetic) into the bonds in starches and sugars (chemical energy) using Photosynthesis
Other energy conversions
oIn an electric motor electromagnetic energy is converted to mechanical energy
oIn a battery chemical energy is converted into electromagnetic energy
oMechanical energy of water falling can be converted to electrical energy in a generator
Hydroelectric Power
Forms of Alternative Energy
Energy Conversions
bull In an automobile engine fuel is burned to convert chemical energy into heat energy The heat energy is then changed into mechanical energy
Chemical Heat Mechanical
The Law of Conservation of Energy
bull Man can neither create nor destroy Energy by ordinary meansoIt can only be converted from one form to another
oIf energy seems to disappear then scientists look for it ndash leading to many important discoveries
Law of Conservation of Energy
bull In 1905 Albert Einstein said that mass and energy can be converted into each other
bull He showed that if matter is destroyed energy is created and if energy is destroyed mass is created
bull E=MC2 bull M=mass C=speed of light
Power = measure of Energybull Work = Force x Distancebull Rate of doing Work orbull Amount of Workunit of timebull Power= WorkTime
bull Power = (Force x Distance)Time
bull Power Units = Watts bull 1Watt=1Joulesec or (1Nmsec)bull 1 Kilowatt = 1000 wattsbull 1 Horsepower = 746 watts
Thermal Energy (Heat) differs from
Temperature
Heat vs Temperaturebull Heat content is the TOTAL
KINETIC ENERGY of the particles in a sample
bull Temperature is the AVERAGE KINETIC ENERGY of the particles in a sample
Which has more Heat and which has the highest temperature
Insulatorsbull There are
thousands of air bubbles trapped in the styrofoam which slows down the heat flow through the layer
Insulation How do the Polar Bears stay warm in
the snow Their dense fine fir traps an air layer next to
their skin
Home Insulationbull The pink fiberglass
fibers trap air in the mat of insulation preventing heat from escaping in the winter or heat from entering during the summer Insulation
Highly Insulating Windows
bull Two or three panes between inside and outside air
bull Insulation is supplied by the Dead Air Space
Image source Southwall Technologies
Heat Transferbull Occurs three waysoConductionoConvectionoRadiation
bull The transfer of heat by direct contact between objects or particles
bull Motion of solid atoms or molecules carried from particle to particle
bull Heat transferred by the movement of molecules within liquid or gaseous substance
bull Warm rises cool sinks
bull A circular motion begins from warmer areas rising due to decreased density moving toward cooler areas which fall because of increased density
bull Wind and Major Weather patterns are caused and move largely because of these convection currents
bull Heat transferred through space
bull MATTER is not needed for radiation
bull EXAMPLE The sunrsquos rays carrying visible light and UV light causing sunburn
Radiationbull Transfer of heat through
electromagnetic radiation (light from stars or light bulbs)
bull Transferred in all directionsbull Matter is not requiredbull Dark or dull objects absorb
more than light or shiny objects do
Temperature
bull Temperature is a measure of the average KE of the particles in a sample of matter
Temperature Conversions
bull oC to oF oF = (95)oC + 32
bull oF to oC oC = 59(oF ndash 32)
bull oC to K K = oC + 273bull K to oC oC = K ndash 273
Going from Celsius to Fahrenheit
Convert 37 oC to oFoF = (95)oC + 32oF = (95)37oC + 32 = 666 + 32 = 986oF
Going from Fahrenheit to CelsiusConvert 68oF to oC
oC = 59(oF ndash 32)oC = 59(68 ndash 32)
= 59(36)
= 20 oC
Going from Kelvin to CelsiusConvert 310 K to oC
oC = K ndash 273oC = 310 ndash 273
= 37oC
Thermal Energybull Which beaker of water has more thermal
energyo B - same temperature but more mass
200 mL
80ordmC
A400 mL
80ordmC
B
Thermal energy relationships a As temperature increases so does
thermal energy (because the kinetic energy of the particles increased)
b Even if the temperature doesnrsquot change the thermal energy in a more massive substance is higher (because it is a total
measure of energy)
c Energy always travels from a high concentration(warm) to a lower concentration(cool) of heat
Land heats up and cools down faster than water The temperature of the water helps keep the
land temperature stable
Thermal Expansionbull Additional heat content causes matter to expandbull Loss of heat content causes matter to contractbull Faster particles take up more space
Sample Problem Thermal Expansion
bull What will be the new volume of 200ml of 20degC water if the temperature is raised to 90degC
bull ∆V = 3σ ∆T Vo
bull = 3 x 69e-6degC x 70degC x 200ml
bull = 2898ml
bull Vnew = Vold + ∆V
bull Vnew = 200ml + 2898ml = 202898ml
Specific heat(CH2O) is the amount of heat required to raise the temperature of 1 kg of a material by one degree (Cdeg or K)
1) C(H2O) = 4184 J kg Cdeg
= 418 kJ kg Cdeg
2) C(sand) = 664 J kg CdegThis is why land heats up quickly during the day and
cools quickly at night and why water takes longer
How to calculate changes in thermal energy
Q = m x Cp x T
Q = quantity of thermal energy
m = mass of substance
T = change in temperature (Tf ndash Ti)
Cp = specific heat of substance(p)
Heat TransferHow much heat is required to warm
230 g of water from 12degC to 90degC
GIVENm = 230 gTi = 12degC
Tf = 90degC
Q = C(H2O)= 4184 JgmiddotoC
WORKQ = mmiddotTmiddotCp
m = 230 gT = 90degC - 12degC = 78degCQ = (230g)(78˚C)(4184 JgmiddotoC)Q = 75061 J
Calorimeters are used to measure the specific heat of a substance
Professional Kingrsquos Ridge
Laws of Thermodynamics
bull First Law Energy is always conservedo Energy added to a system may do two things
bull Increase the total thermal energy of the systembull Do work on the system
o Example Bicycle Pump puts air into tire(work) and heats the air(thermal)
bull Second Law Heat can travel from cold to hot ONLY if work is done on the systemo Example The compressor in a refrigerator
bull Third Law We will never reach Absolute Zero
Uses of Heatbull Heat Engines
o External Combustion Engines Fuel is burned outside of the engine
bull Steam Engine
Internal Combustiono Internal Combustion Engines Fuel is burned inside of the engine
bull Car engines
o 4 stroke engine Pistons are moving up and downbull Intake moving down intake valve open fuel mixture drawn
inbull Compression moving up both valves closedbull Power moving down both valves closed spark igniting fuelbull Exhaust moving up exhaust valve open waste exits
o Cooling system to keep the temperature of the engine within a specific range to prevent damage
o Electrical system Battery is used to start the engine then alternator is used to produce the electricity needed to run the engine and all other systems such as air conditioning
Heating Systemsbull Hot-Water Systemsmdashboilers and radiators -full of hot waterbull Steam Heat Systems-- ldquo -full of hot steambull Electric Heat Systemsmdashproducing heat(lightbulb)bull Forced Air Heating Systemsmdashmost homes todaym burning a fuel
and blowing the warmed air aroundbull Solar Heating using sunlight to heat water and homes
o Passivemdashallowing sunlight to enter home most efficiently and trapping it
o Activemdashcollecting solar energy then heating the home with the energy
bull Heat Pumps evaporators condensers amp coolanto Home Heatingmdashdrawing heat from the warm eartho Refrigeratormdashdrawing heat from the warm food and warm airo Air Conditionermdashdrawing heat from the warm room
Gravitational Potential Energy
bull Potential energy dependent on height is called Gravitational Potential Energy (a form of mechanical energy)
Gravitational Potential Energy
bull If you stand on a 3-meter diving board you have 3 times the GPE than you had on a 1-meter diving board
bull GPE=Weight x Height
bull (pounds) x (feet)bull or (Newtons) x (meters)
bull GPE = (M)(Ag) (H)bull M=Kg Ag =98msec2H=m
Kinetic ndash Potential Energy Conversion
Cars are mechanically pulled to the peak which is the point of maximum potential energy the car has minimum kinetic energy As position is exchanged for speed potential is converted to kinetic energy
Ball slows down
Ball speeds up
Forms of Energy
bull The five main forms of energy areoHeatoChemicaloElectromagneticoNuclearoMechanical
Heat Energybull The internal motion of the
atoms is called heat energy because moving particles produce heat
bull Heat energy can be produced by friction
bull Heat energy causes changes in temperature and phase of any form of matter
Chemical Energy
bull Chemical Energy is required to bond atoms together
bull And when bonds are broken energy can be released or absorbed
bull Exothermic = energy released
bull Endothermic=energy absorbed
Chemical Energy
bull Fossil Fuels and our Food are forms of energy stored in chemical bondsbull The Energy came from nuclear
fusion on our Sun and was photosynthesized by plants and stored in plant and animal life
Formation of Fossil Fuels
bull Petroleum and Natural gas are both products of millions of years of decomposing Marine life both animal and plant
bull Coal is similar but mostly from terrestrial plant life
Where does Coal come from
Electromagnetic Energybull Electricity -- carried in
wiresbull Light -- Each of the colors
of light (ROY G BIV) represents a different amount of electromagnetic energy
bull X-rays amp Cosmic Raysbull TV amp Radio wavesbull Laser light
Nuclear Energybull When the nucleus
splits (Fission) nuclear energy is released in the form of heat energy and light energy
bull Nuclear energy is also released when nuclei collide at high speeds and join (Fusion)
bull MOST CONCENTRATED
Mechanical Energy
bull When work is done to an object it acquires energy The energy it acquires is known as mechanical energy
Mechanical Energy
bull When you kick a football you give mechanical energy to the football to make it move
Energy Conversionbull Energy can be changed from one form to another Changes in the form of energy are called energy conversions
bull Good Examples on Pages 418-419
Energy conversionsbull All forms of energy can be
converted into other formsoThe sunrsquos energy through solar
cells can be converted directly into electricity(Photovoltaic energy)
oGreen plants convert the sunrsquos energy (electromagnetic) into the bonds in starches and sugars (chemical energy) using Photosynthesis
Other energy conversions
oIn an electric motor electromagnetic energy is converted to mechanical energy
oIn a battery chemical energy is converted into electromagnetic energy
oMechanical energy of water falling can be converted to electrical energy in a generator
Hydroelectric Power
Forms of Alternative Energy
Energy Conversions
bull In an automobile engine fuel is burned to convert chemical energy into heat energy The heat energy is then changed into mechanical energy
Chemical Heat Mechanical
The Law of Conservation of Energy
bull Man can neither create nor destroy Energy by ordinary meansoIt can only be converted from one form to another
oIf energy seems to disappear then scientists look for it ndash leading to many important discoveries
Law of Conservation of Energy
bull In 1905 Albert Einstein said that mass and energy can be converted into each other
bull He showed that if matter is destroyed energy is created and if energy is destroyed mass is created
bull E=MC2 bull M=mass C=speed of light
Power = measure of Energybull Work = Force x Distancebull Rate of doing Work orbull Amount of Workunit of timebull Power= WorkTime
bull Power = (Force x Distance)Time
bull Power Units = Watts bull 1Watt=1Joulesec or (1Nmsec)bull 1 Kilowatt = 1000 wattsbull 1 Horsepower = 746 watts
Thermal Energy (Heat) differs from
Temperature
Heat vs Temperaturebull Heat content is the TOTAL
KINETIC ENERGY of the particles in a sample
bull Temperature is the AVERAGE KINETIC ENERGY of the particles in a sample
Which has more Heat and which has the highest temperature
Insulatorsbull There are
thousands of air bubbles trapped in the styrofoam which slows down the heat flow through the layer
Insulation How do the Polar Bears stay warm in
the snow Their dense fine fir traps an air layer next to
their skin
Home Insulationbull The pink fiberglass
fibers trap air in the mat of insulation preventing heat from escaping in the winter or heat from entering during the summer Insulation
Highly Insulating Windows
bull Two or three panes between inside and outside air
bull Insulation is supplied by the Dead Air Space
Image source Southwall Technologies
Heat Transferbull Occurs three waysoConductionoConvectionoRadiation
bull The transfer of heat by direct contact between objects or particles
bull Motion of solid atoms or molecules carried from particle to particle
bull Heat transferred by the movement of molecules within liquid or gaseous substance
bull Warm rises cool sinks
bull A circular motion begins from warmer areas rising due to decreased density moving toward cooler areas which fall because of increased density
bull Wind and Major Weather patterns are caused and move largely because of these convection currents
bull Heat transferred through space
bull MATTER is not needed for radiation
bull EXAMPLE The sunrsquos rays carrying visible light and UV light causing sunburn
Radiationbull Transfer of heat through
electromagnetic radiation (light from stars or light bulbs)
bull Transferred in all directionsbull Matter is not requiredbull Dark or dull objects absorb
more than light or shiny objects do
Temperature
bull Temperature is a measure of the average KE of the particles in a sample of matter
Temperature Conversions
bull oC to oF oF = (95)oC + 32
bull oF to oC oC = 59(oF ndash 32)
bull oC to K K = oC + 273bull K to oC oC = K ndash 273
Going from Celsius to Fahrenheit
Convert 37 oC to oFoF = (95)oC + 32oF = (95)37oC + 32 = 666 + 32 = 986oF
Going from Fahrenheit to CelsiusConvert 68oF to oC
oC = 59(oF ndash 32)oC = 59(68 ndash 32)
= 59(36)
= 20 oC
Going from Kelvin to CelsiusConvert 310 K to oC
oC = K ndash 273oC = 310 ndash 273
= 37oC
Thermal Energybull Which beaker of water has more thermal
energyo B - same temperature but more mass
200 mL
80ordmC
A400 mL
80ordmC
B
Thermal energy relationships a As temperature increases so does
thermal energy (because the kinetic energy of the particles increased)
b Even if the temperature doesnrsquot change the thermal energy in a more massive substance is higher (because it is a total
measure of energy)
c Energy always travels from a high concentration(warm) to a lower concentration(cool) of heat
Land heats up and cools down faster than water The temperature of the water helps keep the
land temperature stable
Thermal Expansionbull Additional heat content causes matter to expandbull Loss of heat content causes matter to contractbull Faster particles take up more space
Sample Problem Thermal Expansion
bull What will be the new volume of 200ml of 20degC water if the temperature is raised to 90degC
bull ∆V = 3σ ∆T Vo
bull = 3 x 69e-6degC x 70degC x 200ml
bull = 2898ml
bull Vnew = Vold + ∆V
bull Vnew = 200ml + 2898ml = 202898ml
Specific heat(CH2O) is the amount of heat required to raise the temperature of 1 kg of a material by one degree (Cdeg or K)
1) C(H2O) = 4184 J kg Cdeg
= 418 kJ kg Cdeg
2) C(sand) = 664 J kg CdegThis is why land heats up quickly during the day and
cools quickly at night and why water takes longer
How to calculate changes in thermal energy
Q = m x Cp x T
Q = quantity of thermal energy
m = mass of substance
T = change in temperature (Tf ndash Ti)
Cp = specific heat of substance(p)
Heat TransferHow much heat is required to warm
230 g of water from 12degC to 90degC
GIVENm = 230 gTi = 12degC
Tf = 90degC
Q = C(H2O)= 4184 JgmiddotoC
WORKQ = mmiddotTmiddotCp
m = 230 gT = 90degC - 12degC = 78degCQ = (230g)(78˚C)(4184 JgmiddotoC)Q = 75061 J
Calorimeters are used to measure the specific heat of a substance
Professional Kingrsquos Ridge
Laws of Thermodynamics
bull First Law Energy is always conservedo Energy added to a system may do two things
bull Increase the total thermal energy of the systembull Do work on the system
o Example Bicycle Pump puts air into tire(work) and heats the air(thermal)
bull Second Law Heat can travel from cold to hot ONLY if work is done on the systemo Example The compressor in a refrigerator
bull Third Law We will never reach Absolute Zero
Uses of Heatbull Heat Engines
o External Combustion Engines Fuel is burned outside of the engine
bull Steam Engine
Internal Combustiono Internal Combustion Engines Fuel is burned inside of the engine
bull Car engines
o 4 stroke engine Pistons are moving up and downbull Intake moving down intake valve open fuel mixture drawn
inbull Compression moving up both valves closedbull Power moving down both valves closed spark igniting fuelbull Exhaust moving up exhaust valve open waste exits
o Cooling system to keep the temperature of the engine within a specific range to prevent damage
o Electrical system Battery is used to start the engine then alternator is used to produce the electricity needed to run the engine and all other systems such as air conditioning
Heating Systemsbull Hot-Water Systemsmdashboilers and radiators -full of hot waterbull Steam Heat Systems-- ldquo -full of hot steambull Electric Heat Systemsmdashproducing heat(lightbulb)bull Forced Air Heating Systemsmdashmost homes todaym burning a fuel
and blowing the warmed air aroundbull Solar Heating using sunlight to heat water and homes
o Passivemdashallowing sunlight to enter home most efficiently and trapping it
o Activemdashcollecting solar energy then heating the home with the energy
bull Heat Pumps evaporators condensers amp coolanto Home Heatingmdashdrawing heat from the warm eartho Refrigeratormdashdrawing heat from the warm food and warm airo Air Conditionermdashdrawing heat from the warm room
Gravitational Potential Energy
bull If you stand on a 3-meter diving board you have 3 times the GPE than you had on a 1-meter diving board
bull GPE=Weight x Height
bull (pounds) x (feet)bull or (Newtons) x (meters)
bull GPE = (M)(Ag) (H)bull M=Kg Ag =98msec2H=m
Kinetic ndash Potential Energy Conversion
Cars are mechanically pulled to the peak which is the point of maximum potential energy the car has minimum kinetic energy As position is exchanged for speed potential is converted to kinetic energy
Ball slows down
Ball speeds up
Forms of Energy
bull The five main forms of energy areoHeatoChemicaloElectromagneticoNuclearoMechanical
Heat Energybull The internal motion of the
atoms is called heat energy because moving particles produce heat
bull Heat energy can be produced by friction
bull Heat energy causes changes in temperature and phase of any form of matter
Chemical Energy
bull Chemical Energy is required to bond atoms together
bull And when bonds are broken energy can be released or absorbed
bull Exothermic = energy released
bull Endothermic=energy absorbed
Chemical Energy
bull Fossil Fuels and our Food are forms of energy stored in chemical bondsbull The Energy came from nuclear
fusion on our Sun and was photosynthesized by plants and stored in plant and animal life
Formation of Fossil Fuels
bull Petroleum and Natural gas are both products of millions of years of decomposing Marine life both animal and plant
bull Coal is similar but mostly from terrestrial plant life
Where does Coal come from
Electromagnetic Energybull Electricity -- carried in
wiresbull Light -- Each of the colors
of light (ROY G BIV) represents a different amount of electromagnetic energy
bull X-rays amp Cosmic Raysbull TV amp Radio wavesbull Laser light
Nuclear Energybull When the nucleus
splits (Fission) nuclear energy is released in the form of heat energy and light energy
bull Nuclear energy is also released when nuclei collide at high speeds and join (Fusion)
bull MOST CONCENTRATED
Mechanical Energy
bull When work is done to an object it acquires energy The energy it acquires is known as mechanical energy
Mechanical Energy
bull When you kick a football you give mechanical energy to the football to make it move
Energy Conversionbull Energy can be changed from one form to another Changes in the form of energy are called energy conversions
bull Good Examples on Pages 418-419
Energy conversionsbull All forms of energy can be
converted into other formsoThe sunrsquos energy through solar
cells can be converted directly into electricity(Photovoltaic energy)
oGreen plants convert the sunrsquos energy (electromagnetic) into the bonds in starches and sugars (chemical energy) using Photosynthesis
Other energy conversions
oIn an electric motor electromagnetic energy is converted to mechanical energy
oIn a battery chemical energy is converted into electromagnetic energy
oMechanical energy of water falling can be converted to electrical energy in a generator
Hydroelectric Power
Forms of Alternative Energy
Energy Conversions
bull In an automobile engine fuel is burned to convert chemical energy into heat energy The heat energy is then changed into mechanical energy
Chemical Heat Mechanical
The Law of Conservation of Energy
bull Man can neither create nor destroy Energy by ordinary meansoIt can only be converted from one form to another
oIf energy seems to disappear then scientists look for it ndash leading to many important discoveries
Law of Conservation of Energy
bull In 1905 Albert Einstein said that mass and energy can be converted into each other
bull He showed that if matter is destroyed energy is created and if energy is destroyed mass is created
bull E=MC2 bull M=mass C=speed of light
Power = measure of Energybull Work = Force x Distancebull Rate of doing Work orbull Amount of Workunit of timebull Power= WorkTime
bull Power = (Force x Distance)Time
bull Power Units = Watts bull 1Watt=1Joulesec or (1Nmsec)bull 1 Kilowatt = 1000 wattsbull 1 Horsepower = 746 watts
Thermal Energy (Heat) differs from
Temperature
Heat vs Temperaturebull Heat content is the TOTAL
KINETIC ENERGY of the particles in a sample
bull Temperature is the AVERAGE KINETIC ENERGY of the particles in a sample
Which has more Heat and which has the highest temperature
Insulatorsbull There are
thousands of air bubbles trapped in the styrofoam which slows down the heat flow through the layer
Insulation How do the Polar Bears stay warm in
the snow Their dense fine fir traps an air layer next to
their skin
Home Insulationbull The pink fiberglass
fibers trap air in the mat of insulation preventing heat from escaping in the winter or heat from entering during the summer Insulation
Highly Insulating Windows
bull Two or three panes between inside and outside air
bull Insulation is supplied by the Dead Air Space
Image source Southwall Technologies
Heat Transferbull Occurs three waysoConductionoConvectionoRadiation
bull The transfer of heat by direct contact between objects or particles
bull Motion of solid atoms or molecules carried from particle to particle
bull Heat transferred by the movement of molecules within liquid or gaseous substance
bull Warm rises cool sinks
bull A circular motion begins from warmer areas rising due to decreased density moving toward cooler areas which fall because of increased density
bull Wind and Major Weather patterns are caused and move largely because of these convection currents
bull Heat transferred through space
bull MATTER is not needed for radiation
bull EXAMPLE The sunrsquos rays carrying visible light and UV light causing sunburn
Radiationbull Transfer of heat through
electromagnetic radiation (light from stars or light bulbs)
bull Transferred in all directionsbull Matter is not requiredbull Dark or dull objects absorb
more than light or shiny objects do
Temperature
bull Temperature is a measure of the average KE of the particles in a sample of matter
Temperature Conversions
bull oC to oF oF = (95)oC + 32
bull oF to oC oC = 59(oF ndash 32)
bull oC to K K = oC + 273bull K to oC oC = K ndash 273
Going from Celsius to Fahrenheit
Convert 37 oC to oFoF = (95)oC + 32oF = (95)37oC + 32 = 666 + 32 = 986oF
Going from Fahrenheit to CelsiusConvert 68oF to oC
oC = 59(oF ndash 32)oC = 59(68 ndash 32)
= 59(36)
= 20 oC
Going from Kelvin to CelsiusConvert 310 K to oC
oC = K ndash 273oC = 310 ndash 273
= 37oC
Thermal Energybull Which beaker of water has more thermal
energyo B - same temperature but more mass
200 mL
80ordmC
A400 mL
80ordmC
B
Thermal energy relationships a As temperature increases so does
thermal energy (because the kinetic energy of the particles increased)
b Even if the temperature doesnrsquot change the thermal energy in a more massive substance is higher (because it is a total
measure of energy)
c Energy always travels from a high concentration(warm) to a lower concentration(cool) of heat
Land heats up and cools down faster than water The temperature of the water helps keep the
land temperature stable
Thermal Expansionbull Additional heat content causes matter to expandbull Loss of heat content causes matter to contractbull Faster particles take up more space
Sample Problem Thermal Expansion
bull What will be the new volume of 200ml of 20degC water if the temperature is raised to 90degC
bull ∆V = 3σ ∆T Vo
bull = 3 x 69e-6degC x 70degC x 200ml
bull = 2898ml
bull Vnew = Vold + ∆V
bull Vnew = 200ml + 2898ml = 202898ml
Specific heat(CH2O) is the amount of heat required to raise the temperature of 1 kg of a material by one degree (Cdeg or K)
1) C(H2O) = 4184 J kg Cdeg
= 418 kJ kg Cdeg
2) C(sand) = 664 J kg CdegThis is why land heats up quickly during the day and
cools quickly at night and why water takes longer
How to calculate changes in thermal energy
Q = m x Cp x T
Q = quantity of thermal energy
m = mass of substance
T = change in temperature (Tf ndash Ti)
Cp = specific heat of substance(p)
Heat TransferHow much heat is required to warm
230 g of water from 12degC to 90degC
GIVENm = 230 gTi = 12degC
Tf = 90degC
Q = C(H2O)= 4184 JgmiddotoC
WORKQ = mmiddotTmiddotCp
m = 230 gT = 90degC - 12degC = 78degCQ = (230g)(78˚C)(4184 JgmiddotoC)Q = 75061 J
Calorimeters are used to measure the specific heat of a substance
Professional Kingrsquos Ridge
Laws of Thermodynamics
bull First Law Energy is always conservedo Energy added to a system may do two things
bull Increase the total thermal energy of the systembull Do work on the system
o Example Bicycle Pump puts air into tire(work) and heats the air(thermal)
bull Second Law Heat can travel from cold to hot ONLY if work is done on the systemo Example The compressor in a refrigerator
bull Third Law We will never reach Absolute Zero
Uses of Heatbull Heat Engines
o External Combustion Engines Fuel is burned outside of the engine
bull Steam Engine
Internal Combustiono Internal Combustion Engines Fuel is burned inside of the engine
bull Car engines
o 4 stroke engine Pistons are moving up and downbull Intake moving down intake valve open fuel mixture drawn
inbull Compression moving up both valves closedbull Power moving down both valves closed spark igniting fuelbull Exhaust moving up exhaust valve open waste exits
o Cooling system to keep the temperature of the engine within a specific range to prevent damage
o Electrical system Battery is used to start the engine then alternator is used to produce the electricity needed to run the engine and all other systems such as air conditioning
Heating Systemsbull Hot-Water Systemsmdashboilers and radiators -full of hot waterbull Steam Heat Systems-- ldquo -full of hot steambull Electric Heat Systemsmdashproducing heat(lightbulb)bull Forced Air Heating Systemsmdashmost homes todaym burning a fuel
and blowing the warmed air aroundbull Solar Heating using sunlight to heat water and homes
o Passivemdashallowing sunlight to enter home most efficiently and trapping it
o Activemdashcollecting solar energy then heating the home with the energy
bull Heat Pumps evaporators condensers amp coolanto Home Heatingmdashdrawing heat from the warm eartho Refrigeratormdashdrawing heat from the warm food and warm airo Air Conditionermdashdrawing heat from the warm room
Kinetic ndash Potential Energy Conversion
Cars are mechanically pulled to the peak which is the point of maximum potential energy the car has minimum kinetic energy As position is exchanged for speed potential is converted to kinetic energy
Ball slows down
Ball speeds up
Forms of Energy
bull The five main forms of energy areoHeatoChemicaloElectromagneticoNuclearoMechanical
Heat Energybull The internal motion of the
atoms is called heat energy because moving particles produce heat
bull Heat energy can be produced by friction
bull Heat energy causes changes in temperature and phase of any form of matter
Chemical Energy
bull Chemical Energy is required to bond atoms together
bull And when bonds are broken energy can be released or absorbed
bull Exothermic = energy released
bull Endothermic=energy absorbed
Chemical Energy
bull Fossil Fuels and our Food are forms of energy stored in chemical bondsbull The Energy came from nuclear
fusion on our Sun and was photosynthesized by plants and stored in plant and animal life
Formation of Fossil Fuels
bull Petroleum and Natural gas are both products of millions of years of decomposing Marine life both animal and plant
bull Coal is similar but mostly from terrestrial plant life
Where does Coal come from
Electromagnetic Energybull Electricity -- carried in
wiresbull Light -- Each of the colors
of light (ROY G BIV) represents a different amount of electromagnetic energy
bull X-rays amp Cosmic Raysbull TV amp Radio wavesbull Laser light
Nuclear Energybull When the nucleus
splits (Fission) nuclear energy is released in the form of heat energy and light energy
bull Nuclear energy is also released when nuclei collide at high speeds and join (Fusion)
bull MOST CONCENTRATED
Mechanical Energy
bull When work is done to an object it acquires energy The energy it acquires is known as mechanical energy
Mechanical Energy
bull When you kick a football you give mechanical energy to the football to make it move
Energy Conversionbull Energy can be changed from one form to another Changes in the form of energy are called energy conversions
bull Good Examples on Pages 418-419
Energy conversionsbull All forms of energy can be
converted into other formsoThe sunrsquos energy through solar
cells can be converted directly into electricity(Photovoltaic energy)
oGreen plants convert the sunrsquos energy (electromagnetic) into the bonds in starches and sugars (chemical energy) using Photosynthesis
Other energy conversions
oIn an electric motor electromagnetic energy is converted to mechanical energy
oIn a battery chemical energy is converted into electromagnetic energy
oMechanical energy of water falling can be converted to electrical energy in a generator
Hydroelectric Power
Forms of Alternative Energy
Energy Conversions
bull In an automobile engine fuel is burned to convert chemical energy into heat energy The heat energy is then changed into mechanical energy
Chemical Heat Mechanical
The Law of Conservation of Energy
bull Man can neither create nor destroy Energy by ordinary meansoIt can only be converted from one form to another
oIf energy seems to disappear then scientists look for it ndash leading to many important discoveries
Law of Conservation of Energy
bull In 1905 Albert Einstein said that mass and energy can be converted into each other
bull He showed that if matter is destroyed energy is created and if energy is destroyed mass is created
bull E=MC2 bull M=mass C=speed of light
Power = measure of Energybull Work = Force x Distancebull Rate of doing Work orbull Amount of Workunit of timebull Power= WorkTime
bull Power = (Force x Distance)Time
bull Power Units = Watts bull 1Watt=1Joulesec or (1Nmsec)bull 1 Kilowatt = 1000 wattsbull 1 Horsepower = 746 watts
Thermal Energy (Heat) differs from
Temperature
Heat vs Temperaturebull Heat content is the TOTAL
KINETIC ENERGY of the particles in a sample
bull Temperature is the AVERAGE KINETIC ENERGY of the particles in a sample
Which has more Heat and which has the highest temperature
Insulatorsbull There are
thousands of air bubbles trapped in the styrofoam which slows down the heat flow through the layer
Insulation How do the Polar Bears stay warm in
the snow Their dense fine fir traps an air layer next to
their skin
Home Insulationbull The pink fiberglass
fibers trap air in the mat of insulation preventing heat from escaping in the winter or heat from entering during the summer Insulation
Highly Insulating Windows
bull Two or three panes between inside and outside air
bull Insulation is supplied by the Dead Air Space
Image source Southwall Technologies
Heat Transferbull Occurs three waysoConductionoConvectionoRadiation
bull The transfer of heat by direct contact between objects or particles
bull Motion of solid atoms or molecules carried from particle to particle
bull Heat transferred by the movement of molecules within liquid or gaseous substance
bull Warm rises cool sinks
bull A circular motion begins from warmer areas rising due to decreased density moving toward cooler areas which fall because of increased density
bull Wind and Major Weather patterns are caused and move largely because of these convection currents
bull Heat transferred through space
bull MATTER is not needed for radiation
bull EXAMPLE The sunrsquos rays carrying visible light and UV light causing sunburn
Radiationbull Transfer of heat through
electromagnetic radiation (light from stars or light bulbs)
bull Transferred in all directionsbull Matter is not requiredbull Dark or dull objects absorb
more than light or shiny objects do
Temperature
bull Temperature is a measure of the average KE of the particles in a sample of matter
Temperature Conversions
bull oC to oF oF = (95)oC + 32
bull oF to oC oC = 59(oF ndash 32)
bull oC to K K = oC + 273bull K to oC oC = K ndash 273
Going from Celsius to Fahrenheit
Convert 37 oC to oFoF = (95)oC + 32oF = (95)37oC + 32 = 666 + 32 = 986oF
Going from Fahrenheit to CelsiusConvert 68oF to oC
oC = 59(oF ndash 32)oC = 59(68 ndash 32)
= 59(36)
= 20 oC
Going from Kelvin to CelsiusConvert 310 K to oC
oC = K ndash 273oC = 310 ndash 273
= 37oC
Thermal Energybull Which beaker of water has more thermal
energyo B - same temperature but more mass
200 mL
80ordmC
A400 mL
80ordmC
B
Thermal energy relationships a As temperature increases so does
thermal energy (because the kinetic energy of the particles increased)
b Even if the temperature doesnrsquot change the thermal energy in a more massive substance is higher (because it is a total
measure of energy)
c Energy always travels from a high concentration(warm) to a lower concentration(cool) of heat
Land heats up and cools down faster than water The temperature of the water helps keep the
land temperature stable
Thermal Expansionbull Additional heat content causes matter to expandbull Loss of heat content causes matter to contractbull Faster particles take up more space
Sample Problem Thermal Expansion
bull What will be the new volume of 200ml of 20degC water if the temperature is raised to 90degC
bull ∆V = 3σ ∆T Vo
bull = 3 x 69e-6degC x 70degC x 200ml
bull = 2898ml
bull Vnew = Vold + ∆V
bull Vnew = 200ml + 2898ml = 202898ml
Specific heat(CH2O) is the amount of heat required to raise the temperature of 1 kg of a material by one degree (Cdeg or K)
1) C(H2O) = 4184 J kg Cdeg
= 418 kJ kg Cdeg
2) C(sand) = 664 J kg CdegThis is why land heats up quickly during the day and
cools quickly at night and why water takes longer
How to calculate changes in thermal energy
Q = m x Cp x T
Q = quantity of thermal energy
m = mass of substance
T = change in temperature (Tf ndash Ti)
Cp = specific heat of substance(p)
Heat TransferHow much heat is required to warm
230 g of water from 12degC to 90degC
GIVENm = 230 gTi = 12degC
Tf = 90degC
Q = C(H2O)= 4184 JgmiddotoC
WORKQ = mmiddotTmiddotCp
m = 230 gT = 90degC - 12degC = 78degCQ = (230g)(78˚C)(4184 JgmiddotoC)Q = 75061 J
Calorimeters are used to measure the specific heat of a substance
Professional Kingrsquos Ridge
Laws of Thermodynamics
bull First Law Energy is always conservedo Energy added to a system may do two things
bull Increase the total thermal energy of the systembull Do work on the system
o Example Bicycle Pump puts air into tire(work) and heats the air(thermal)
bull Second Law Heat can travel from cold to hot ONLY if work is done on the systemo Example The compressor in a refrigerator
bull Third Law We will never reach Absolute Zero
Uses of Heatbull Heat Engines
o External Combustion Engines Fuel is burned outside of the engine
bull Steam Engine
Internal Combustiono Internal Combustion Engines Fuel is burned inside of the engine
bull Car engines
o 4 stroke engine Pistons are moving up and downbull Intake moving down intake valve open fuel mixture drawn
inbull Compression moving up both valves closedbull Power moving down both valves closed spark igniting fuelbull Exhaust moving up exhaust valve open waste exits
o Cooling system to keep the temperature of the engine within a specific range to prevent damage
o Electrical system Battery is used to start the engine then alternator is used to produce the electricity needed to run the engine and all other systems such as air conditioning
Heating Systemsbull Hot-Water Systemsmdashboilers and radiators -full of hot waterbull Steam Heat Systems-- ldquo -full of hot steambull Electric Heat Systemsmdashproducing heat(lightbulb)bull Forced Air Heating Systemsmdashmost homes todaym burning a fuel
and blowing the warmed air aroundbull Solar Heating using sunlight to heat water and homes
o Passivemdashallowing sunlight to enter home most efficiently and trapping it
o Activemdashcollecting solar energy then heating the home with the energy
bull Heat Pumps evaporators condensers amp coolanto Home Heatingmdashdrawing heat from the warm eartho Refrigeratormdashdrawing heat from the warm food and warm airo Air Conditionermdashdrawing heat from the warm room
Ball slows down
Ball speeds up
Forms of Energy
bull The five main forms of energy areoHeatoChemicaloElectromagneticoNuclearoMechanical
Heat Energybull The internal motion of the
atoms is called heat energy because moving particles produce heat
bull Heat energy can be produced by friction
bull Heat energy causes changes in temperature and phase of any form of matter
Chemical Energy
bull Chemical Energy is required to bond atoms together
bull And when bonds are broken energy can be released or absorbed
bull Exothermic = energy released
bull Endothermic=energy absorbed
Chemical Energy
bull Fossil Fuels and our Food are forms of energy stored in chemical bondsbull The Energy came from nuclear
fusion on our Sun and was photosynthesized by plants and stored in plant and animal life
Formation of Fossil Fuels
bull Petroleum and Natural gas are both products of millions of years of decomposing Marine life both animal and plant
bull Coal is similar but mostly from terrestrial plant life
Where does Coal come from
Electromagnetic Energybull Electricity -- carried in
wiresbull Light -- Each of the colors
of light (ROY G BIV) represents a different amount of electromagnetic energy
bull X-rays amp Cosmic Raysbull TV amp Radio wavesbull Laser light
Nuclear Energybull When the nucleus
splits (Fission) nuclear energy is released in the form of heat energy and light energy
bull Nuclear energy is also released when nuclei collide at high speeds and join (Fusion)
bull MOST CONCENTRATED
Mechanical Energy
bull When work is done to an object it acquires energy The energy it acquires is known as mechanical energy
Mechanical Energy
bull When you kick a football you give mechanical energy to the football to make it move
Energy Conversionbull Energy can be changed from one form to another Changes in the form of energy are called energy conversions
bull Good Examples on Pages 418-419
Energy conversionsbull All forms of energy can be
converted into other formsoThe sunrsquos energy through solar
cells can be converted directly into electricity(Photovoltaic energy)
oGreen plants convert the sunrsquos energy (electromagnetic) into the bonds in starches and sugars (chemical energy) using Photosynthesis
Other energy conversions
oIn an electric motor electromagnetic energy is converted to mechanical energy
oIn a battery chemical energy is converted into electromagnetic energy
oMechanical energy of water falling can be converted to electrical energy in a generator
Hydroelectric Power
Forms of Alternative Energy
Energy Conversions
bull In an automobile engine fuel is burned to convert chemical energy into heat energy The heat energy is then changed into mechanical energy
Chemical Heat Mechanical
The Law of Conservation of Energy
bull Man can neither create nor destroy Energy by ordinary meansoIt can only be converted from one form to another
oIf energy seems to disappear then scientists look for it ndash leading to many important discoveries
Law of Conservation of Energy
bull In 1905 Albert Einstein said that mass and energy can be converted into each other
bull He showed that if matter is destroyed energy is created and if energy is destroyed mass is created
bull E=MC2 bull M=mass C=speed of light
Power = measure of Energybull Work = Force x Distancebull Rate of doing Work orbull Amount of Workunit of timebull Power= WorkTime
bull Power = (Force x Distance)Time
bull Power Units = Watts bull 1Watt=1Joulesec or (1Nmsec)bull 1 Kilowatt = 1000 wattsbull 1 Horsepower = 746 watts
Thermal Energy (Heat) differs from
Temperature
Heat vs Temperaturebull Heat content is the TOTAL
KINETIC ENERGY of the particles in a sample
bull Temperature is the AVERAGE KINETIC ENERGY of the particles in a sample
Which has more Heat and which has the highest temperature
Insulatorsbull There are
thousands of air bubbles trapped in the styrofoam which slows down the heat flow through the layer
Insulation How do the Polar Bears stay warm in
the snow Their dense fine fir traps an air layer next to
their skin
Home Insulationbull The pink fiberglass
fibers trap air in the mat of insulation preventing heat from escaping in the winter or heat from entering during the summer Insulation
Highly Insulating Windows
bull Two or three panes between inside and outside air
bull Insulation is supplied by the Dead Air Space
Image source Southwall Technologies
Heat Transferbull Occurs three waysoConductionoConvectionoRadiation
bull The transfer of heat by direct contact between objects or particles
bull Motion of solid atoms or molecules carried from particle to particle
bull Heat transferred by the movement of molecules within liquid or gaseous substance
bull Warm rises cool sinks
bull A circular motion begins from warmer areas rising due to decreased density moving toward cooler areas which fall because of increased density
bull Wind and Major Weather patterns are caused and move largely because of these convection currents
bull Heat transferred through space
bull MATTER is not needed for radiation
bull EXAMPLE The sunrsquos rays carrying visible light and UV light causing sunburn
Radiationbull Transfer of heat through
electromagnetic radiation (light from stars or light bulbs)
bull Transferred in all directionsbull Matter is not requiredbull Dark or dull objects absorb
more than light or shiny objects do
Temperature
bull Temperature is a measure of the average KE of the particles in a sample of matter
Temperature Conversions
bull oC to oF oF = (95)oC + 32
bull oF to oC oC = 59(oF ndash 32)
bull oC to K K = oC + 273bull K to oC oC = K ndash 273
Going from Celsius to Fahrenheit
Convert 37 oC to oFoF = (95)oC + 32oF = (95)37oC + 32 = 666 + 32 = 986oF
Going from Fahrenheit to CelsiusConvert 68oF to oC
oC = 59(oF ndash 32)oC = 59(68 ndash 32)
= 59(36)
= 20 oC
Going from Kelvin to CelsiusConvert 310 K to oC
oC = K ndash 273oC = 310 ndash 273
= 37oC
Thermal Energybull Which beaker of water has more thermal
energyo B - same temperature but more mass
200 mL
80ordmC
A400 mL
80ordmC
B
Thermal energy relationships a As temperature increases so does
thermal energy (because the kinetic energy of the particles increased)
b Even if the temperature doesnrsquot change the thermal energy in a more massive substance is higher (because it is a total
measure of energy)
c Energy always travels from a high concentration(warm) to a lower concentration(cool) of heat
Land heats up and cools down faster than water The temperature of the water helps keep the
land temperature stable
Thermal Expansionbull Additional heat content causes matter to expandbull Loss of heat content causes matter to contractbull Faster particles take up more space
Sample Problem Thermal Expansion
bull What will be the new volume of 200ml of 20degC water if the temperature is raised to 90degC
bull ∆V = 3σ ∆T Vo
bull = 3 x 69e-6degC x 70degC x 200ml
bull = 2898ml
bull Vnew = Vold + ∆V
bull Vnew = 200ml + 2898ml = 202898ml
Specific heat(CH2O) is the amount of heat required to raise the temperature of 1 kg of a material by one degree (Cdeg or K)
1) C(H2O) = 4184 J kg Cdeg
= 418 kJ kg Cdeg
2) C(sand) = 664 J kg CdegThis is why land heats up quickly during the day and
cools quickly at night and why water takes longer
How to calculate changes in thermal energy
Q = m x Cp x T
Q = quantity of thermal energy
m = mass of substance
T = change in temperature (Tf ndash Ti)
Cp = specific heat of substance(p)
Heat TransferHow much heat is required to warm
230 g of water from 12degC to 90degC
GIVENm = 230 gTi = 12degC
Tf = 90degC
Q = C(H2O)= 4184 JgmiddotoC
WORKQ = mmiddotTmiddotCp
m = 230 gT = 90degC - 12degC = 78degCQ = (230g)(78˚C)(4184 JgmiddotoC)Q = 75061 J
Calorimeters are used to measure the specific heat of a substance
Professional Kingrsquos Ridge
Laws of Thermodynamics
bull First Law Energy is always conservedo Energy added to a system may do two things
bull Increase the total thermal energy of the systembull Do work on the system
o Example Bicycle Pump puts air into tire(work) and heats the air(thermal)
bull Second Law Heat can travel from cold to hot ONLY if work is done on the systemo Example The compressor in a refrigerator
bull Third Law We will never reach Absolute Zero
Uses of Heatbull Heat Engines
o External Combustion Engines Fuel is burned outside of the engine
bull Steam Engine
Internal Combustiono Internal Combustion Engines Fuel is burned inside of the engine
bull Car engines
o 4 stroke engine Pistons are moving up and downbull Intake moving down intake valve open fuel mixture drawn
inbull Compression moving up both valves closedbull Power moving down both valves closed spark igniting fuelbull Exhaust moving up exhaust valve open waste exits
o Cooling system to keep the temperature of the engine within a specific range to prevent damage
o Electrical system Battery is used to start the engine then alternator is used to produce the electricity needed to run the engine and all other systems such as air conditioning
Heating Systemsbull Hot-Water Systemsmdashboilers and radiators -full of hot waterbull Steam Heat Systems-- ldquo -full of hot steambull Electric Heat Systemsmdashproducing heat(lightbulb)bull Forced Air Heating Systemsmdashmost homes todaym burning a fuel
and blowing the warmed air aroundbull Solar Heating using sunlight to heat water and homes
o Passivemdashallowing sunlight to enter home most efficiently and trapping it
o Activemdashcollecting solar energy then heating the home with the energy
bull Heat Pumps evaporators condensers amp coolanto Home Heatingmdashdrawing heat from the warm eartho Refrigeratormdashdrawing heat from the warm food and warm airo Air Conditionermdashdrawing heat from the warm room
Forms of Energy
bull The five main forms of energy areoHeatoChemicaloElectromagneticoNuclearoMechanical
Heat Energybull The internal motion of the
atoms is called heat energy because moving particles produce heat
bull Heat energy can be produced by friction
bull Heat energy causes changes in temperature and phase of any form of matter
Chemical Energy
bull Chemical Energy is required to bond atoms together
bull And when bonds are broken energy can be released or absorbed
bull Exothermic = energy released
bull Endothermic=energy absorbed
Chemical Energy
bull Fossil Fuels and our Food are forms of energy stored in chemical bondsbull The Energy came from nuclear
fusion on our Sun and was photosynthesized by plants and stored in plant and animal life
Formation of Fossil Fuels
bull Petroleum and Natural gas are both products of millions of years of decomposing Marine life both animal and plant
bull Coal is similar but mostly from terrestrial plant life
Where does Coal come from
Electromagnetic Energybull Electricity -- carried in
wiresbull Light -- Each of the colors
of light (ROY G BIV) represents a different amount of electromagnetic energy
bull X-rays amp Cosmic Raysbull TV amp Radio wavesbull Laser light
Nuclear Energybull When the nucleus
splits (Fission) nuclear energy is released in the form of heat energy and light energy
bull Nuclear energy is also released when nuclei collide at high speeds and join (Fusion)
bull MOST CONCENTRATED
Mechanical Energy
bull When work is done to an object it acquires energy The energy it acquires is known as mechanical energy
Mechanical Energy
bull When you kick a football you give mechanical energy to the football to make it move
Energy Conversionbull Energy can be changed from one form to another Changes in the form of energy are called energy conversions
bull Good Examples on Pages 418-419
Energy conversionsbull All forms of energy can be
converted into other formsoThe sunrsquos energy through solar
cells can be converted directly into electricity(Photovoltaic energy)
oGreen plants convert the sunrsquos energy (electromagnetic) into the bonds in starches and sugars (chemical energy) using Photosynthesis
Other energy conversions
oIn an electric motor electromagnetic energy is converted to mechanical energy
oIn a battery chemical energy is converted into electromagnetic energy
oMechanical energy of water falling can be converted to electrical energy in a generator
Hydroelectric Power
Forms of Alternative Energy
Energy Conversions
bull In an automobile engine fuel is burned to convert chemical energy into heat energy The heat energy is then changed into mechanical energy
Chemical Heat Mechanical
The Law of Conservation of Energy
bull Man can neither create nor destroy Energy by ordinary meansoIt can only be converted from one form to another
oIf energy seems to disappear then scientists look for it ndash leading to many important discoveries
Law of Conservation of Energy
bull In 1905 Albert Einstein said that mass and energy can be converted into each other
bull He showed that if matter is destroyed energy is created and if energy is destroyed mass is created
bull E=MC2 bull M=mass C=speed of light
Power = measure of Energybull Work = Force x Distancebull Rate of doing Work orbull Amount of Workunit of timebull Power= WorkTime
bull Power = (Force x Distance)Time
bull Power Units = Watts bull 1Watt=1Joulesec or (1Nmsec)bull 1 Kilowatt = 1000 wattsbull 1 Horsepower = 746 watts
Thermal Energy (Heat) differs from
Temperature
Heat vs Temperaturebull Heat content is the TOTAL
KINETIC ENERGY of the particles in a sample
bull Temperature is the AVERAGE KINETIC ENERGY of the particles in a sample
Which has more Heat and which has the highest temperature
Insulatorsbull There are
thousands of air bubbles trapped in the styrofoam which slows down the heat flow through the layer
Insulation How do the Polar Bears stay warm in
the snow Their dense fine fir traps an air layer next to
their skin
Home Insulationbull The pink fiberglass
fibers trap air in the mat of insulation preventing heat from escaping in the winter or heat from entering during the summer Insulation
Highly Insulating Windows
bull Two or three panes between inside and outside air
bull Insulation is supplied by the Dead Air Space
Image source Southwall Technologies
Heat Transferbull Occurs three waysoConductionoConvectionoRadiation
bull The transfer of heat by direct contact between objects or particles
bull Motion of solid atoms or molecules carried from particle to particle
bull Heat transferred by the movement of molecules within liquid or gaseous substance
bull Warm rises cool sinks
bull A circular motion begins from warmer areas rising due to decreased density moving toward cooler areas which fall because of increased density
bull Wind and Major Weather patterns are caused and move largely because of these convection currents
bull Heat transferred through space
bull MATTER is not needed for radiation
bull EXAMPLE The sunrsquos rays carrying visible light and UV light causing sunburn
Radiationbull Transfer of heat through
electromagnetic radiation (light from stars or light bulbs)
bull Transferred in all directionsbull Matter is not requiredbull Dark or dull objects absorb
more than light or shiny objects do
Temperature
bull Temperature is a measure of the average KE of the particles in a sample of matter
Temperature Conversions
bull oC to oF oF = (95)oC + 32
bull oF to oC oC = 59(oF ndash 32)
bull oC to K K = oC + 273bull K to oC oC = K ndash 273
Going from Celsius to Fahrenheit
Convert 37 oC to oFoF = (95)oC + 32oF = (95)37oC + 32 = 666 + 32 = 986oF
Going from Fahrenheit to CelsiusConvert 68oF to oC
oC = 59(oF ndash 32)oC = 59(68 ndash 32)
= 59(36)
= 20 oC
Going from Kelvin to CelsiusConvert 310 K to oC
oC = K ndash 273oC = 310 ndash 273
= 37oC
Thermal Energybull Which beaker of water has more thermal
energyo B - same temperature but more mass
200 mL
80ordmC
A400 mL
80ordmC
B
Thermal energy relationships a As temperature increases so does
thermal energy (because the kinetic energy of the particles increased)
b Even if the temperature doesnrsquot change the thermal energy in a more massive substance is higher (because it is a total
measure of energy)
c Energy always travels from a high concentration(warm) to a lower concentration(cool) of heat
Land heats up and cools down faster than water The temperature of the water helps keep the
land temperature stable
Thermal Expansionbull Additional heat content causes matter to expandbull Loss of heat content causes matter to contractbull Faster particles take up more space
Sample Problem Thermal Expansion
bull What will be the new volume of 200ml of 20degC water if the temperature is raised to 90degC
bull ∆V = 3σ ∆T Vo
bull = 3 x 69e-6degC x 70degC x 200ml
bull = 2898ml
bull Vnew = Vold + ∆V
bull Vnew = 200ml + 2898ml = 202898ml
Specific heat(CH2O) is the amount of heat required to raise the temperature of 1 kg of a material by one degree (Cdeg or K)
1) C(H2O) = 4184 J kg Cdeg
= 418 kJ kg Cdeg
2) C(sand) = 664 J kg CdegThis is why land heats up quickly during the day and
cools quickly at night and why water takes longer
How to calculate changes in thermal energy
Q = m x Cp x T
Q = quantity of thermal energy
m = mass of substance
T = change in temperature (Tf ndash Ti)
Cp = specific heat of substance(p)
Heat TransferHow much heat is required to warm
230 g of water from 12degC to 90degC
GIVENm = 230 gTi = 12degC
Tf = 90degC
Q = C(H2O)= 4184 JgmiddotoC
WORKQ = mmiddotTmiddotCp
m = 230 gT = 90degC - 12degC = 78degCQ = (230g)(78˚C)(4184 JgmiddotoC)Q = 75061 J
Calorimeters are used to measure the specific heat of a substance
Professional Kingrsquos Ridge
Laws of Thermodynamics
bull First Law Energy is always conservedo Energy added to a system may do two things
bull Increase the total thermal energy of the systembull Do work on the system
o Example Bicycle Pump puts air into tire(work) and heats the air(thermal)
bull Second Law Heat can travel from cold to hot ONLY if work is done on the systemo Example The compressor in a refrigerator
bull Third Law We will never reach Absolute Zero
Uses of Heatbull Heat Engines
o External Combustion Engines Fuel is burned outside of the engine
bull Steam Engine
Internal Combustiono Internal Combustion Engines Fuel is burned inside of the engine
bull Car engines
o 4 stroke engine Pistons are moving up and downbull Intake moving down intake valve open fuel mixture drawn
inbull Compression moving up both valves closedbull Power moving down both valves closed spark igniting fuelbull Exhaust moving up exhaust valve open waste exits
o Cooling system to keep the temperature of the engine within a specific range to prevent damage
o Electrical system Battery is used to start the engine then alternator is used to produce the electricity needed to run the engine and all other systems such as air conditioning
Heating Systemsbull Hot-Water Systemsmdashboilers and radiators -full of hot waterbull Steam Heat Systems-- ldquo -full of hot steambull Electric Heat Systemsmdashproducing heat(lightbulb)bull Forced Air Heating Systemsmdashmost homes todaym burning a fuel
and blowing the warmed air aroundbull Solar Heating using sunlight to heat water and homes
o Passivemdashallowing sunlight to enter home most efficiently and trapping it
o Activemdashcollecting solar energy then heating the home with the energy
bull Heat Pumps evaporators condensers amp coolanto Home Heatingmdashdrawing heat from the warm eartho Refrigeratormdashdrawing heat from the warm food and warm airo Air Conditionermdashdrawing heat from the warm room
Heat Energybull The internal motion of the
atoms is called heat energy because moving particles produce heat
bull Heat energy can be produced by friction
bull Heat energy causes changes in temperature and phase of any form of matter
Chemical Energy
bull Chemical Energy is required to bond atoms together
bull And when bonds are broken energy can be released or absorbed
bull Exothermic = energy released
bull Endothermic=energy absorbed
Chemical Energy
bull Fossil Fuels and our Food are forms of energy stored in chemical bondsbull The Energy came from nuclear
fusion on our Sun and was photosynthesized by plants and stored in plant and animal life
Formation of Fossil Fuels
bull Petroleum and Natural gas are both products of millions of years of decomposing Marine life both animal and plant
bull Coal is similar but mostly from terrestrial plant life
Where does Coal come from
Electromagnetic Energybull Electricity -- carried in
wiresbull Light -- Each of the colors
of light (ROY G BIV) represents a different amount of electromagnetic energy
bull X-rays amp Cosmic Raysbull TV amp Radio wavesbull Laser light
Nuclear Energybull When the nucleus
splits (Fission) nuclear energy is released in the form of heat energy and light energy
bull Nuclear energy is also released when nuclei collide at high speeds and join (Fusion)
bull MOST CONCENTRATED
Mechanical Energy
bull When work is done to an object it acquires energy The energy it acquires is known as mechanical energy
Mechanical Energy
bull When you kick a football you give mechanical energy to the football to make it move
Energy Conversionbull Energy can be changed from one form to another Changes in the form of energy are called energy conversions
bull Good Examples on Pages 418-419
Energy conversionsbull All forms of energy can be
converted into other formsoThe sunrsquos energy through solar
cells can be converted directly into electricity(Photovoltaic energy)
oGreen plants convert the sunrsquos energy (electromagnetic) into the bonds in starches and sugars (chemical energy) using Photosynthesis
Other energy conversions
oIn an electric motor electromagnetic energy is converted to mechanical energy
oIn a battery chemical energy is converted into electromagnetic energy
oMechanical energy of water falling can be converted to electrical energy in a generator
Hydroelectric Power
Forms of Alternative Energy
Energy Conversions
bull In an automobile engine fuel is burned to convert chemical energy into heat energy The heat energy is then changed into mechanical energy
Chemical Heat Mechanical
The Law of Conservation of Energy
bull Man can neither create nor destroy Energy by ordinary meansoIt can only be converted from one form to another
oIf energy seems to disappear then scientists look for it ndash leading to many important discoveries
Law of Conservation of Energy
bull In 1905 Albert Einstein said that mass and energy can be converted into each other
bull He showed that if matter is destroyed energy is created and if energy is destroyed mass is created
bull E=MC2 bull M=mass C=speed of light
Power = measure of Energybull Work = Force x Distancebull Rate of doing Work orbull Amount of Workunit of timebull Power= WorkTime
bull Power = (Force x Distance)Time
bull Power Units = Watts bull 1Watt=1Joulesec or (1Nmsec)bull 1 Kilowatt = 1000 wattsbull 1 Horsepower = 746 watts
Thermal Energy (Heat) differs from
Temperature
Heat vs Temperaturebull Heat content is the TOTAL
KINETIC ENERGY of the particles in a sample
bull Temperature is the AVERAGE KINETIC ENERGY of the particles in a sample
Which has more Heat and which has the highest temperature
Insulatorsbull There are
thousands of air bubbles trapped in the styrofoam which slows down the heat flow through the layer
Insulation How do the Polar Bears stay warm in
the snow Their dense fine fir traps an air layer next to
their skin
Home Insulationbull The pink fiberglass
fibers trap air in the mat of insulation preventing heat from escaping in the winter or heat from entering during the summer Insulation
Highly Insulating Windows
bull Two or three panes between inside and outside air
bull Insulation is supplied by the Dead Air Space
Image source Southwall Technologies
Heat Transferbull Occurs three waysoConductionoConvectionoRadiation
bull The transfer of heat by direct contact between objects or particles
bull Motion of solid atoms or molecules carried from particle to particle
bull Heat transferred by the movement of molecules within liquid or gaseous substance
bull Warm rises cool sinks
bull A circular motion begins from warmer areas rising due to decreased density moving toward cooler areas which fall because of increased density
bull Wind and Major Weather patterns are caused and move largely because of these convection currents
bull Heat transferred through space
bull MATTER is not needed for radiation
bull EXAMPLE The sunrsquos rays carrying visible light and UV light causing sunburn
Radiationbull Transfer of heat through
electromagnetic radiation (light from stars or light bulbs)
bull Transferred in all directionsbull Matter is not requiredbull Dark or dull objects absorb
more than light or shiny objects do
Temperature
bull Temperature is a measure of the average KE of the particles in a sample of matter
Temperature Conversions
bull oC to oF oF = (95)oC + 32
bull oF to oC oC = 59(oF ndash 32)
bull oC to K K = oC + 273bull K to oC oC = K ndash 273
Going from Celsius to Fahrenheit
Convert 37 oC to oFoF = (95)oC + 32oF = (95)37oC + 32 = 666 + 32 = 986oF
Going from Fahrenheit to CelsiusConvert 68oF to oC
oC = 59(oF ndash 32)oC = 59(68 ndash 32)
= 59(36)
= 20 oC
Going from Kelvin to CelsiusConvert 310 K to oC
oC = K ndash 273oC = 310 ndash 273
= 37oC
Thermal Energybull Which beaker of water has more thermal
energyo B - same temperature but more mass
200 mL
80ordmC
A400 mL
80ordmC
B
Thermal energy relationships a As temperature increases so does
thermal energy (because the kinetic energy of the particles increased)
b Even if the temperature doesnrsquot change the thermal energy in a more massive substance is higher (because it is a total
measure of energy)
c Energy always travels from a high concentration(warm) to a lower concentration(cool) of heat
Land heats up and cools down faster than water The temperature of the water helps keep the
land temperature stable
Thermal Expansionbull Additional heat content causes matter to expandbull Loss of heat content causes matter to contractbull Faster particles take up more space
Sample Problem Thermal Expansion
bull What will be the new volume of 200ml of 20degC water if the temperature is raised to 90degC
bull ∆V = 3σ ∆T Vo
bull = 3 x 69e-6degC x 70degC x 200ml
bull = 2898ml
bull Vnew = Vold + ∆V
bull Vnew = 200ml + 2898ml = 202898ml
Specific heat(CH2O) is the amount of heat required to raise the temperature of 1 kg of a material by one degree (Cdeg or K)
1) C(H2O) = 4184 J kg Cdeg
= 418 kJ kg Cdeg
2) C(sand) = 664 J kg CdegThis is why land heats up quickly during the day and
cools quickly at night and why water takes longer
How to calculate changes in thermal energy
Q = m x Cp x T
Q = quantity of thermal energy
m = mass of substance
T = change in temperature (Tf ndash Ti)
Cp = specific heat of substance(p)
Heat TransferHow much heat is required to warm
230 g of water from 12degC to 90degC
GIVENm = 230 gTi = 12degC
Tf = 90degC
Q = C(H2O)= 4184 JgmiddotoC
WORKQ = mmiddotTmiddotCp
m = 230 gT = 90degC - 12degC = 78degCQ = (230g)(78˚C)(4184 JgmiddotoC)Q = 75061 J
Calorimeters are used to measure the specific heat of a substance
Professional Kingrsquos Ridge
Laws of Thermodynamics
bull First Law Energy is always conservedo Energy added to a system may do two things
bull Increase the total thermal energy of the systembull Do work on the system
o Example Bicycle Pump puts air into tire(work) and heats the air(thermal)
bull Second Law Heat can travel from cold to hot ONLY if work is done on the systemo Example The compressor in a refrigerator
bull Third Law We will never reach Absolute Zero
Uses of Heatbull Heat Engines
o External Combustion Engines Fuel is burned outside of the engine
bull Steam Engine
Internal Combustiono Internal Combustion Engines Fuel is burned inside of the engine
bull Car engines
o 4 stroke engine Pistons are moving up and downbull Intake moving down intake valve open fuel mixture drawn
inbull Compression moving up both valves closedbull Power moving down both valves closed spark igniting fuelbull Exhaust moving up exhaust valve open waste exits
o Cooling system to keep the temperature of the engine within a specific range to prevent damage
o Electrical system Battery is used to start the engine then alternator is used to produce the electricity needed to run the engine and all other systems such as air conditioning
Heating Systemsbull Hot-Water Systemsmdashboilers and radiators -full of hot waterbull Steam Heat Systems-- ldquo -full of hot steambull Electric Heat Systemsmdashproducing heat(lightbulb)bull Forced Air Heating Systemsmdashmost homes todaym burning a fuel
and blowing the warmed air aroundbull Solar Heating using sunlight to heat water and homes
o Passivemdashallowing sunlight to enter home most efficiently and trapping it
o Activemdashcollecting solar energy then heating the home with the energy
bull Heat Pumps evaporators condensers amp coolanto Home Heatingmdashdrawing heat from the warm eartho Refrigeratormdashdrawing heat from the warm food and warm airo Air Conditionermdashdrawing heat from the warm room
Chemical Energy
bull Chemical Energy is required to bond atoms together
bull And when bonds are broken energy can be released or absorbed
bull Exothermic = energy released
bull Endothermic=energy absorbed
Chemical Energy
bull Fossil Fuels and our Food are forms of energy stored in chemical bondsbull The Energy came from nuclear
fusion on our Sun and was photosynthesized by plants and stored in plant and animal life
Formation of Fossil Fuels
bull Petroleum and Natural gas are both products of millions of years of decomposing Marine life both animal and plant
bull Coal is similar but mostly from terrestrial plant life
Where does Coal come from
Electromagnetic Energybull Electricity -- carried in
wiresbull Light -- Each of the colors
of light (ROY G BIV) represents a different amount of electromagnetic energy
bull X-rays amp Cosmic Raysbull TV amp Radio wavesbull Laser light
Nuclear Energybull When the nucleus
splits (Fission) nuclear energy is released in the form of heat energy and light energy
bull Nuclear energy is also released when nuclei collide at high speeds and join (Fusion)
bull MOST CONCENTRATED
Mechanical Energy
bull When work is done to an object it acquires energy The energy it acquires is known as mechanical energy
Mechanical Energy
bull When you kick a football you give mechanical energy to the football to make it move
Energy Conversionbull Energy can be changed from one form to another Changes in the form of energy are called energy conversions
bull Good Examples on Pages 418-419
Energy conversionsbull All forms of energy can be
converted into other formsoThe sunrsquos energy through solar
cells can be converted directly into electricity(Photovoltaic energy)
oGreen plants convert the sunrsquos energy (electromagnetic) into the bonds in starches and sugars (chemical energy) using Photosynthesis
Other energy conversions
oIn an electric motor electromagnetic energy is converted to mechanical energy
oIn a battery chemical energy is converted into electromagnetic energy
oMechanical energy of water falling can be converted to electrical energy in a generator
Hydroelectric Power
Forms of Alternative Energy
Energy Conversions
bull In an automobile engine fuel is burned to convert chemical energy into heat energy The heat energy is then changed into mechanical energy
Chemical Heat Mechanical
The Law of Conservation of Energy
bull Man can neither create nor destroy Energy by ordinary meansoIt can only be converted from one form to another
oIf energy seems to disappear then scientists look for it ndash leading to many important discoveries
Law of Conservation of Energy
bull In 1905 Albert Einstein said that mass and energy can be converted into each other
bull He showed that if matter is destroyed energy is created and if energy is destroyed mass is created
bull E=MC2 bull M=mass C=speed of light
Power = measure of Energybull Work = Force x Distancebull Rate of doing Work orbull Amount of Workunit of timebull Power= WorkTime
bull Power = (Force x Distance)Time
bull Power Units = Watts bull 1Watt=1Joulesec or (1Nmsec)bull 1 Kilowatt = 1000 wattsbull 1 Horsepower = 746 watts
Thermal Energy (Heat) differs from
Temperature
Heat vs Temperaturebull Heat content is the TOTAL
KINETIC ENERGY of the particles in a sample
bull Temperature is the AVERAGE KINETIC ENERGY of the particles in a sample
Which has more Heat and which has the highest temperature
Insulatorsbull There are
thousands of air bubbles trapped in the styrofoam which slows down the heat flow through the layer
Insulation How do the Polar Bears stay warm in
the snow Their dense fine fir traps an air layer next to
their skin
Home Insulationbull The pink fiberglass
fibers trap air in the mat of insulation preventing heat from escaping in the winter or heat from entering during the summer Insulation
Highly Insulating Windows
bull Two or three panes between inside and outside air
bull Insulation is supplied by the Dead Air Space
Image source Southwall Technologies
Heat Transferbull Occurs three waysoConductionoConvectionoRadiation
bull The transfer of heat by direct contact between objects or particles
bull Motion of solid atoms or molecules carried from particle to particle
bull Heat transferred by the movement of molecules within liquid or gaseous substance
bull Warm rises cool sinks
bull A circular motion begins from warmer areas rising due to decreased density moving toward cooler areas which fall because of increased density
bull Wind and Major Weather patterns are caused and move largely because of these convection currents
bull Heat transferred through space
bull MATTER is not needed for radiation
bull EXAMPLE The sunrsquos rays carrying visible light and UV light causing sunburn
Radiationbull Transfer of heat through
electromagnetic radiation (light from stars or light bulbs)
bull Transferred in all directionsbull Matter is not requiredbull Dark or dull objects absorb
more than light or shiny objects do
Temperature
bull Temperature is a measure of the average KE of the particles in a sample of matter
Temperature Conversions
bull oC to oF oF = (95)oC + 32
bull oF to oC oC = 59(oF ndash 32)
bull oC to K K = oC + 273bull K to oC oC = K ndash 273
Going from Celsius to Fahrenheit
Convert 37 oC to oFoF = (95)oC + 32oF = (95)37oC + 32 = 666 + 32 = 986oF
Going from Fahrenheit to CelsiusConvert 68oF to oC
oC = 59(oF ndash 32)oC = 59(68 ndash 32)
= 59(36)
= 20 oC
Going from Kelvin to CelsiusConvert 310 K to oC
oC = K ndash 273oC = 310 ndash 273
= 37oC
Thermal Energybull Which beaker of water has more thermal
energyo B - same temperature but more mass
200 mL
80ordmC
A400 mL
80ordmC
B
Thermal energy relationships a As temperature increases so does
thermal energy (because the kinetic energy of the particles increased)
b Even if the temperature doesnrsquot change the thermal energy in a more massive substance is higher (because it is a total
measure of energy)
c Energy always travels from a high concentration(warm) to a lower concentration(cool) of heat
Land heats up and cools down faster than water The temperature of the water helps keep the
land temperature stable
Thermal Expansionbull Additional heat content causes matter to expandbull Loss of heat content causes matter to contractbull Faster particles take up more space
Sample Problem Thermal Expansion
bull What will be the new volume of 200ml of 20degC water if the temperature is raised to 90degC
bull ∆V = 3σ ∆T Vo
bull = 3 x 69e-6degC x 70degC x 200ml
bull = 2898ml
bull Vnew = Vold + ∆V
bull Vnew = 200ml + 2898ml = 202898ml
Specific heat(CH2O) is the amount of heat required to raise the temperature of 1 kg of a material by one degree (Cdeg or K)
1) C(H2O) = 4184 J kg Cdeg
= 418 kJ kg Cdeg
2) C(sand) = 664 J kg CdegThis is why land heats up quickly during the day and
cools quickly at night and why water takes longer
How to calculate changes in thermal energy
Q = m x Cp x T
Q = quantity of thermal energy
m = mass of substance
T = change in temperature (Tf ndash Ti)
Cp = specific heat of substance(p)
Heat TransferHow much heat is required to warm
230 g of water from 12degC to 90degC
GIVENm = 230 gTi = 12degC
Tf = 90degC
Q = C(H2O)= 4184 JgmiddotoC
WORKQ = mmiddotTmiddotCp
m = 230 gT = 90degC - 12degC = 78degCQ = (230g)(78˚C)(4184 JgmiddotoC)Q = 75061 J
Calorimeters are used to measure the specific heat of a substance
Professional Kingrsquos Ridge
Laws of Thermodynamics
bull First Law Energy is always conservedo Energy added to a system may do two things
bull Increase the total thermal energy of the systembull Do work on the system
o Example Bicycle Pump puts air into tire(work) and heats the air(thermal)
bull Second Law Heat can travel from cold to hot ONLY if work is done on the systemo Example The compressor in a refrigerator
bull Third Law We will never reach Absolute Zero
Uses of Heatbull Heat Engines
o External Combustion Engines Fuel is burned outside of the engine
bull Steam Engine
Internal Combustiono Internal Combustion Engines Fuel is burned inside of the engine
bull Car engines
o 4 stroke engine Pistons are moving up and downbull Intake moving down intake valve open fuel mixture drawn
inbull Compression moving up both valves closedbull Power moving down both valves closed spark igniting fuelbull Exhaust moving up exhaust valve open waste exits
o Cooling system to keep the temperature of the engine within a specific range to prevent damage
o Electrical system Battery is used to start the engine then alternator is used to produce the electricity needed to run the engine and all other systems such as air conditioning
Heating Systemsbull Hot-Water Systemsmdashboilers and radiators -full of hot waterbull Steam Heat Systems-- ldquo -full of hot steambull Electric Heat Systemsmdashproducing heat(lightbulb)bull Forced Air Heating Systemsmdashmost homes todaym burning a fuel
and blowing the warmed air aroundbull Solar Heating using sunlight to heat water and homes
o Passivemdashallowing sunlight to enter home most efficiently and trapping it
o Activemdashcollecting solar energy then heating the home with the energy
bull Heat Pumps evaporators condensers amp coolanto Home Heatingmdashdrawing heat from the warm eartho Refrigeratormdashdrawing heat from the warm food and warm airo Air Conditionermdashdrawing heat from the warm room
Chemical Energy
bull Fossil Fuels and our Food are forms of energy stored in chemical bondsbull The Energy came from nuclear
fusion on our Sun and was photosynthesized by plants and stored in plant and animal life
Formation of Fossil Fuels
bull Petroleum and Natural gas are both products of millions of years of decomposing Marine life both animal and plant
bull Coal is similar but mostly from terrestrial plant life
Where does Coal come from
Electromagnetic Energybull Electricity -- carried in
wiresbull Light -- Each of the colors
of light (ROY G BIV) represents a different amount of electromagnetic energy
bull X-rays amp Cosmic Raysbull TV amp Radio wavesbull Laser light
Nuclear Energybull When the nucleus
splits (Fission) nuclear energy is released in the form of heat energy and light energy
bull Nuclear energy is also released when nuclei collide at high speeds and join (Fusion)
bull MOST CONCENTRATED
Mechanical Energy
bull When work is done to an object it acquires energy The energy it acquires is known as mechanical energy
Mechanical Energy
bull When you kick a football you give mechanical energy to the football to make it move
Energy Conversionbull Energy can be changed from one form to another Changes in the form of energy are called energy conversions
bull Good Examples on Pages 418-419
Energy conversionsbull All forms of energy can be
converted into other formsoThe sunrsquos energy through solar
cells can be converted directly into electricity(Photovoltaic energy)
oGreen plants convert the sunrsquos energy (electromagnetic) into the bonds in starches and sugars (chemical energy) using Photosynthesis
Other energy conversions
oIn an electric motor electromagnetic energy is converted to mechanical energy
oIn a battery chemical energy is converted into electromagnetic energy
oMechanical energy of water falling can be converted to electrical energy in a generator
Hydroelectric Power
Forms of Alternative Energy
Energy Conversions
bull In an automobile engine fuel is burned to convert chemical energy into heat energy The heat energy is then changed into mechanical energy
Chemical Heat Mechanical
The Law of Conservation of Energy
bull Man can neither create nor destroy Energy by ordinary meansoIt can only be converted from one form to another
oIf energy seems to disappear then scientists look for it ndash leading to many important discoveries
Law of Conservation of Energy
bull In 1905 Albert Einstein said that mass and energy can be converted into each other
bull He showed that if matter is destroyed energy is created and if energy is destroyed mass is created
bull E=MC2 bull M=mass C=speed of light
Power = measure of Energybull Work = Force x Distancebull Rate of doing Work orbull Amount of Workunit of timebull Power= WorkTime
bull Power = (Force x Distance)Time
bull Power Units = Watts bull 1Watt=1Joulesec or (1Nmsec)bull 1 Kilowatt = 1000 wattsbull 1 Horsepower = 746 watts
Thermal Energy (Heat) differs from
Temperature
Heat vs Temperaturebull Heat content is the TOTAL
KINETIC ENERGY of the particles in a sample
bull Temperature is the AVERAGE KINETIC ENERGY of the particles in a sample
Which has more Heat and which has the highest temperature
Insulatorsbull There are
thousands of air bubbles trapped in the styrofoam which slows down the heat flow through the layer
Insulation How do the Polar Bears stay warm in
the snow Their dense fine fir traps an air layer next to
their skin
Home Insulationbull The pink fiberglass
fibers trap air in the mat of insulation preventing heat from escaping in the winter or heat from entering during the summer Insulation
Highly Insulating Windows
bull Two or three panes between inside and outside air
bull Insulation is supplied by the Dead Air Space
Image source Southwall Technologies
Heat Transferbull Occurs three waysoConductionoConvectionoRadiation
bull The transfer of heat by direct contact between objects or particles
bull Motion of solid atoms or molecules carried from particle to particle
bull Heat transferred by the movement of molecules within liquid or gaseous substance
bull Warm rises cool sinks
bull A circular motion begins from warmer areas rising due to decreased density moving toward cooler areas which fall because of increased density
bull Wind and Major Weather patterns are caused and move largely because of these convection currents
bull Heat transferred through space
bull MATTER is not needed for radiation
bull EXAMPLE The sunrsquos rays carrying visible light and UV light causing sunburn
Radiationbull Transfer of heat through
electromagnetic radiation (light from stars or light bulbs)
bull Transferred in all directionsbull Matter is not requiredbull Dark or dull objects absorb
more than light or shiny objects do
Temperature
bull Temperature is a measure of the average KE of the particles in a sample of matter
Temperature Conversions
bull oC to oF oF = (95)oC + 32
bull oF to oC oC = 59(oF ndash 32)
bull oC to K K = oC + 273bull K to oC oC = K ndash 273
Going from Celsius to Fahrenheit
Convert 37 oC to oFoF = (95)oC + 32oF = (95)37oC + 32 = 666 + 32 = 986oF
Going from Fahrenheit to CelsiusConvert 68oF to oC
oC = 59(oF ndash 32)oC = 59(68 ndash 32)
= 59(36)
= 20 oC
Going from Kelvin to CelsiusConvert 310 K to oC
oC = K ndash 273oC = 310 ndash 273
= 37oC
Thermal Energybull Which beaker of water has more thermal
energyo B - same temperature but more mass
200 mL
80ordmC
A400 mL
80ordmC
B
Thermal energy relationships a As temperature increases so does
thermal energy (because the kinetic energy of the particles increased)
b Even if the temperature doesnrsquot change the thermal energy in a more massive substance is higher (because it is a total
measure of energy)
c Energy always travels from a high concentration(warm) to a lower concentration(cool) of heat
Land heats up and cools down faster than water The temperature of the water helps keep the
land temperature stable
Thermal Expansionbull Additional heat content causes matter to expandbull Loss of heat content causes matter to contractbull Faster particles take up more space
Sample Problem Thermal Expansion
bull What will be the new volume of 200ml of 20degC water if the temperature is raised to 90degC
bull ∆V = 3σ ∆T Vo
bull = 3 x 69e-6degC x 70degC x 200ml
bull = 2898ml
bull Vnew = Vold + ∆V
bull Vnew = 200ml + 2898ml = 202898ml
Specific heat(CH2O) is the amount of heat required to raise the temperature of 1 kg of a material by one degree (Cdeg or K)
1) C(H2O) = 4184 J kg Cdeg
= 418 kJ kg Cdeg
2) C(sand) = 664 J kg CdegThis is why land heats up quickly during the day and
cools quickly at night and why water takes longer
How to calculate changes in thermal energy
Q = m x Cp x T
Q = quantity of thermal energy
m = mass of substance
T = change in temperature (Tf ndash Ti)
Cp = specific heat of substance(p)
Heat TransferHow much heat is required to warm
230 g of water from 12degC to 90degC
GIVENm = 230 gTi = 12degC
Tf = 90degC
Q = C(H2O)= 4184 JgmiddotoC
WORKQ = mmiddotTmiddotCp
m = 230 gT = 90degC - 12degC = 78degCQ = (230g)(78˚C)(4184 JgmiddotoC)Q = 75061 J
Calorimeters are used to measure the specific heat of a substance
Professional Kingrsquos Ridge
Laws of Thermodynamics
bull First Law Energy is always conservedo Energy added to a system may do two things
bull Increase the total thermal energy of the systembull Do work on the system
o Example Bicycle Pump puts air into tire(work) and heats the air(thermal)
bull Second Law Heat can travel from cold to hot ONLY if work is done on the systemo Example The compressor in a refrigerator
bull Third Law We will never reach Absolute Zero
Uses of Heatbull Heat Engines
o External Combustion Engines Fuel is burned outside of the engine
bull Steam Engine
Internal Combustiono Internal Combustion Engines Fuel is burned inside of the engine
bull Car engines
o 4 stroke engine Pistons are moving up and downbull Intake moving down intake valve open fuel mixture drawn
inbull Compression moving up both valves closedbull Power moving down both valves closed spark igniting fuelbull Exhaust moving up exhaust valve open waste exits
o Cooling system to keep the temperature of the engine within a specific range to prevent damage
o Electrical system Battery is used to start the engine then alternator is used to produce the electricity needed to run the engine and all other systems such as air conditioning
Heating Systemsbull Hot-Water Systemsmdashboilers and radiators -full of hot waterbull Steam Heat Systems-- ldquo -full of hot steambull Electric Heat Systemsmdashproducing heat(lightbulb)bull Forced Air Heating Systemsmdashmost homes todaym burning a fuel
and blowing the warmed air aroundbull Solar Heating using sunlight to heat water and homes
o Passivemdashallowing sunlight to enter home most efficiently and trapping it
o Activemdashcollecting solar energy then heating the home with the energy
bull Heat Pumps evaporators condensers amp coolanto Home Heatingmdashdrawing heat from the warm eartho Refrigeratormdashdrawing heat from the warm food and warm airo Air Conditionermdashdrawing heat from the warm room
Formation of Fossil Fuels
bull Petroleum and Natural gas are both products of millions of years of decomposing Marine life both animal and plant
bull Coal is similar but mostly from terrestrial plant life
Where does Coal come from
Electromagnetic Energybull Electricity -- carried in
wiresbull Light -- Each of the colors
of light (ROY G BIV) represents a different amount of electromagnetic energy
bull X-rays amp Cosmic Raysbull TV amp Radio wavesbull Laser light
Nuclear Energybull When the nucleus
splits (Fission) nuclear energy is released in the form of heat energy and light energy
bull Nuclear energy is also released when nuclei collide at high speeds and join (Fusion)
bull MOST CONCENTRATED
Mechanical Energy
bull When work is done to an object it acquires energy The energy it acquires is known as mechanical energy
Mechanical Energy
bull When you kick a football you give mechanical energy to the football to make it move
Energy Conversionbull Energy can be changed from one form to another Changes in the form of energy are called energy conversions
bull Good Examples on Pages 418-419
Energy conversionsbull All forms of energy can be
converted into other formsoThe sunrsquos energy through solar
cells can be converted directly into electricity(Photovoltaic energy)
oGreen plants convert the sunrsquos energy (electromagnetic) into the bonds in starches and sugars (chemical energy) using Photosynthesis
Other energy conversions
oIn an electric motor electromagnetic energy is converted to mechanical energy
oIn a battery chemical energy is converted into electromagnetic energy
oMechanical energy of water falling can be converted to electrical energy in a generator
Hydroelectric Power
Forms of Alternative Energy
Energy Conversions
bull In an automobile engine fuel is burned to convert chemical energy into heat energy The heat energy is then changed into mechanical energy
Chemical Heat Mechanical
The Law of Conservation of Energy
bull Man can neither create nor destroy Energy by ordinary meansoIt can only be converted from one form to another
oIf energy seems to disappear then scientists look for it ndash leading to many important discoveries
Law of Conservation of Energy
bull In 1905 Albert Einstein said that mass and energy can be converted into each other
bull He showed that if matter is destroyed energy is created and if energy is destroyed mass is created
bull E=MC2 bull M=mass C=speed of light
Power = measure of Energybull Work = Force x Distancebull Rate of doing Work orbull Amount of Workunit of timebull Power= WorkTime
bull Power = (Force x Distance)Time
bull Power Units = Watts bull 1Watt=1Joulesec or (1Nmsec)bull 1 Kilowatt = 1000 wattsbull 1 Horsepower = 746 watts
Thermal Energy (Heat) differs from
Temperature
Heat vs Temperaturebull Heat content is the TOTAL
KINETIC ENERGY of the particles in a sample
bull Temperature is the AVERAGE KINETIC ENERGY of the particles in a sample
Which has more Heat and which has the highest temperature
Insulatorsbull There are
thousands of air bubbles trapped in the styrofoam which slows down the heat flow through the layer
Insulation How do the Polar Bears stay warm in
the snow Their dense fine fir traps an air layer next to
their skin
Home Insulationbull The pink fiberglass
fibers trap air in the mat of insulation preventing heat from escaping in the winter or heat from entering during the summer Insulation
Highly Insulating Windows
bull Two or three panes between inside and outside air
bull Insulation is supplied by the Dead Air Space
Image source Southwall Technologies
Heat Transferbull Occurs three waysoConductionoConvectionoRadiation
bull The transfer of heat by direct contact between objects or particles
bull Motion of solid atoms or molecules carried from particle to particle
bull Heat transferred by the movement of molecules within liquid or gaseous substance
bull Warm rises cool sinks
bull A circular motion begins from warmer areas rising due to decreased density moving toward cooler areas which fall because of increased density
bull Wind and Major Weather patterns are caused and move largely because of these convection currents
bull Heat transferred through space
bull MATTER is not needed for radiation
bull EXAMPLE The sunrsquos rays carrying visible light and UV light causing sunburn
Radiationbull Transfer of heat through
electromagnetic radiation (light from stars or light bulbs)
bull Transferred in all directionsbull Matter is not requiredbull Dark or dull objects absorb
more than light or shiny objects do
Temperature
bull Temperature is a measure of the average KE of the particles in a sample of matter
Temperature Conversions
bull oC to oF oF = (95)oC + 32
bull oF to oC oC = 59(oF ndash 32)
bull oC to K K = oC + 273bull K to oC oC = K ndash 273
Going from Celsius to Fahrenheit
Convert 37 oC to oFoF = (95)oC + 32oF = (95)37oC + 32 = 666 + 32 = 986oF
Going from Fahrenheit to CelsiusConvert 68oF to oC
oC = 59(oF ndash 32)oC = 59(68 ndash 32)
= 59(36)
= 20 oC
Going from Kelvin to CelsiusConvert 310 K to oC
oC = K ndash 273oC = 310 ndash 273
= 37oC
Thermal Energybull Which beaker of water has more thermal
energyo B - same temperature but more mass
200 mL
80ordmC
A400 mL
80ordmC
B
Thermal energy relationships a As temperature increases so does
thermal energy (because the kinetic energy of the particles increased)
b Even if the temperature doesnrsquot change the thermal energy in a more massive substance is higher (because it is a total
measure of energy)
c Energy always travels from a high concentration(warm) to a lower concentration(cool) of heat
Land heats up and cools down faster than water The temperature of the water helps keep the
land temperature stable
Thermal Expansionbull Additional heat content causes matter to expandbull Loss of heat content causes matter to contractbull Faster particles take up more space
Sample Problem Thermal Expansion
bull What will be the new volume of 200ml of 20degC water if the temperature is raised to 90degC
bull ∆V = 3σ ∆T Vo
bull = 3 x 69e-6degC x 70degC x 200ml
bull = 2898ml
bull Vnew = Vold + ∆V
bull Vnew = 200ml + 2898ml = 202898ml
Specific heat(CH2O) is the amount of heat required to raise the temperature of 1 kg of a material by one degree (Cdeg or K)
1) C(H2O) = 4184 J kg Cdeg
= 418 kJ kg Cdeg
2) C(sand) = 664 J kg CdegThis is why land heats up quickly during the day and
cools quickly at night and why water takes longer
How to calculate changes in thermal energy
Q = m x Cp x T
Q = quantity of thermal energy
m = mass of substance
T = change in temperature (Tf ndash Ti)
Cp = specific heat of substance(p)
Heat TransferHow much heat is required to warm
230 g of water from 12degC to 90degC
GIVENm = 230 gTi = 12degC
Tf = 90degC
Q = C(H2O)= 4184 JgmiddotoC
WORKQ = mmiddotTmiddotCp
m = 230 gT = 90degC - 12degC = 78degCQ = (230g)(78˚C)(4184 JgmiddotoC)Q = 75061 J
Calorimeters are used to measure the specific heat of a substance
Professional Kingrsquos Ridge
Laws of Thermodynamics
bull First Law Energy is always conservedo Energy added to a system may do two things
bull Increase the total thermal energy of the systembull Do work on the system
o Example Bicycle Pump puts air into tire(work) and heats the air(thermal)
bull Second Law Heat can travel from cold to hot ONLY if work is done on the systemo Example The compressor in a refrigerator
bull Third Law We will never reach Absolute Zero
Uses of Heatbull Heat Engines
o External Combustion Engines Fuel is burned outside of the engine
bull Steam Engine
Internal Combustiono Internal Combustion Engines Fuel is burned inside of the engine
bull Car engines
o 4 stroke engine Pistons are moving up and downbull Intake moving down intake valve open fuel mixture drawn
inbull Compression moving up both valves closedbull Power moving down both valves closed spark igniting fuelbull Exhaust moving up exhaust valve open waste exits
o Cooling system to keep the temperature of the engine within a specific range to prevent damage
o Electrical system Battery is used to start the engine then alternator is used to produce the electricity needed to run the engine and all other systems such as air conditioning
Heating Systemsbull Hot-Water Systemsmdashboilers and radiators -full of hot waterbull Steam Heat Systems-- ldquo -full of hot steambull Electric Heat Systemsmdashproducing heat(lightbulb)bull Forced Air Heating Systemsmdashmost homes todaym burning a fuel
and blowing the warmed air aroundbull Solar Heating using sunlight to heat water and homes
o Passivemdashallowing sunlight to enter home most efficiently and trapping it
o Activemdashcollecting solar energy then heating the home with the energy
bull Heat Pumps evaporators condensers amp coolanto Home Heatingmdashdrawing heat from the warm eartho Refrigeratormdashdrawing heat from the warm food and warm airo Air Conditionermdashdrawing heat from the warm room
Where does Coal come from
Electromagnetic Energybull Electricity -- carried in
wiresbull Light -- Each of the colors
of light (ROY G BIV) represents a different amount of electromagnetic energy
bull X-rays amp Cosmic Raysbull TV amp Radio wavesbull Laser light
Nuclear Energybull When the nucleus
splits (Fission) nuclear energy is released in the form of heat energy and light energy
bull Nuclear energy is also released when nuclei collide at high speeds and join (Fusion)
bull MOST CONCENTRATED
Mechanical Energy
bull When work is done to an object it acquires energy The energy it acquires is known as mechanical energy
Mechanical Energy
bull When you kick a football you give mechanical energy to the football to make it move
Energy Conversionbull Energy can be changed from one form to another Changes in the form of energy are called energy conversions
bull Good Examples on Pages 418-419
Energy conversionsbull All forms of energy can be
converted into other formsoThe sunrsquos energy through solar
cells can be converted directly into electricity(Photovoltaic energy)
oGreen plants convert the sunrsquos energy (electromagnetic) into the bonds in starches and sugars (chemical energy) using Photosynthesis
Other energy conversions
oIn an electric motor electromagnetic energy is converted to mechanical energy
oIn a battery chemical energy is converted into electromagnetic energy
oMechanical energy of water falling can be converted to electrical energy in a generator
Hydroelectric Power
Forms of Alternative Energy
Energy Conversions
bull In an automobile engine fuel is burned to convert chemical energy into heat energy The heat energy is then changed into mechanical energy
Chemical Heat Mechanical
The Law of Conservation of Energy
bull Man can neither create nor destroy Energy by ordinary meansoIt can only be converted from one form to another
oIf energy seems to disappear then scientists look for it ndash leading to many important discoveries
Law of Conservation of Energy
bull In 1905 Albert Einstein said that mass and energy can be converted into each other
bull He showed that if matter is destroyed energy is created and if energy is destroyed mass is created
bull E=MC2 bull M=mass C=speed of light
Power = measure of Energybull Work = Force x Distancebull Rate of doing Work orbull Amount of Workunit of timebull Power= WorkTime
bull Power = (Force x Distance)Time
bull Power Units = Watts bull 1Watt=1Joulesec or (1Nmsec)bull 1 Kilowatt = 1000 wattsbull 1 Horsepower = 746 watts
Thermal Energy (Heat) differs from
Temperature
Heat vs Temperaturebull Heat content is the TOTAL
KINETIC ENERGY of the particles in a sample
bull Temperature is the AVERAGE KINETIC ENERGY of the particles in a sample
Which has more Heat and which has the highest temperature
Insulatorsbull There are
thousands of air bubbles trapped in the styrofoam which slows down the heat flow through the layer
Insulation How do the Polar Bears stay warm in
the snow Their dense fine fir traps an air layer next to
their skin
Home Insulationbull The pink fiberglass
fibers trap air in the mat of insulation preventing heat from escaping in the winter or heat from entering during the summer Insulation
Highly Insulating Windows
bull Two or three panes between inside and outside air
bull Insulation is supplied by the Dead Air Space
Image source Southwall Technologies
Heat Transferbull Occurs three waysoConductionoConvectionoRadiation
bull The transfer of heat by direct contact between objects or particles
bull Motion of solid atoms or molecules carried from particle to particle
bull Heat transferred by the movement of molecules within liquid or gaseous substance
bull Warm rises cool sinks
bull A circular motion begins from warmer areas rising due to decreased density moving toward cooler areas which fall because of increased density
bull Wind and Major Weather patterns are caused and move largely because of these convection currents
bull Heat transferred through space
bull MATTER is not needed for radiation
bull EXAMPLE The sunrsquos rays carrying visible light and UV light causing sunburn
Radiationbull Transfer of heat through
electromagnetic radiation (light from stars or light bulbs)
bull Transferred in all directionsbull Matter is not requiredbull Dark or dull objects absorb
more than light or shiny objects do
Temperature
bull Temperature is a measure of the average KE of the particles in a sample of matter
Temperature Conversions
bull oC to oF oF = (95)oC + 32
bull oF to oC oC = 59(oF ndash 32)
bull oC to K K = oC + 273bull K to oC oC = K ndash 273
Going from Celsius to Fahrenheit
Convert 37 oC to oFoF = (95)oC + 32oF = (95)37oC + 32 = 666 + 32 = 986oF
Going from Fahrenheit to CelsiusConvert 68oF to oC
oC = 59(oF ndash 32)oC = 59(68 ndash 32)
= 59(36)
= 20 oC
Going from Kelvin to CelsiusConvert 310 K to oC
oC = K ndash 273oC = 310 ndash 273
= 37oC
Thermal Energybull Which beaker of water has more thermal
energyo B - same temperature but more mass
200 mL
80ordmC
A400 mL
80ordmC
B
Thermal energy relationships a As temperature increases so does
thermal energy (because the kinetic energy of the particles increased)
b Even if the temperature doesnrsquot change the thermal energy in a more massive substance is higher (because it is a total
measure of energy)
c Energy always travels from a high concentration(warm) to a lower concentration(cool) of heat
Land heats up and cools down faster than water The temperature of the water helps keep the
land temperature stable
Thermal Expansionbull Additional heat content causes matter to expandbull Loss of heat content causes matter to contractbull Faster particles take up more space
Sample Problem Thermal Expansion
bull What will be the new volume of 200ml of 20degC water if the temperature is raised to 90degC
bull ∆V = 3σ ∆T Vo
bull = 3 x 69e-6degC x 70degC x 200ml
bull = 2898ml
bull Vnew = Vold + ∆V
bull Vnew = 200ml + 2898ml = 202898ml
Specific heat(CH2O) is the amount of heat required to raise the temperature of 1 kg of a material by one degree (Cdeg or K)
1) C(H2O) = 4184 J kg Cdeg
= 418 kJ kg Cdeg
2) C(sand) = 664 J kg CdegThis is why land heats up quickly during the day and
cools quickly at night and why water takes longer
How to calculate changes in thermal energy
Q = m x Cp x T
Q = quantity of thermal energy
m = mass of substance
T = change in temperature (Tf ndash Ti)
Cp = specific heat of substance(p)
Heat TransferHow much heat is required to warm
230 g of water from 12degC to 90degC
GIVENm = 230 gTi = 12degC
Tf = 90degC
Q = C(H2O)= 4184 JgmiddotoC
WORKQ = mmiddotTmiddotCp
m = 230 gT = 90degC - 12degC = 78degCQ = (230g)(78˚C)(4184 JgmiddotoC)Q = 75061 J
Calorimeters are used to measure the specific heat of a substance
Professional Kingrsquos Ridge
Laws of Thermodynamics
bull First Law Energy is always conservedo Energy added to a system may do two things
bull Increase the total thermal energy of the systembull Do work on the system
o Example Bicycle Pump puts air into tire(work) and heats the air(thermal)
bull Second Law Heat can travel from cold to hot ONLY if work is done on the systemo Example The compressor in a refrigerator
bull Third Law We will never reach Absolute Zero
Uses of Heatbull Heat Engines
o External Combustion Engines Fuel is burned outside of the engine
bull Steam Engine
Internal Combustiono Internal Combustion Engines Fuel is burned inside of the engine
bull Car engines
o 4 stroke engine Pistons are moving up and downbull Intake moving down intake valve open fuel mixture drawn
inbull Compression moving up both valves closedbull Power moving down both valves closed spark igniting fuelbull Exhaust moving up exhaust valve open waste exits
o Cooling system to keep the temperature of the engine within a specific range to prevent damage
o Electrical system Battery is used to start the engine then alternator is used to produce the electricity needed to run the engine and all other systems such as air conditioning
Heating Systemsbull Hot-Water Systemsmdashboilers and radiators -full of hot waterbull Steam Heat Systems-- ldquo -full of hot steambull Electric Heat Systemsmdashproducing heat(lightbulb)bull Forced Air Heating Systemsmdashmost homes todaym burning a fuel
and blowing the warmed air aroundbull Solar Heating using sunlight to heat water and homes
o Passivemdashallowing sunlight to enter home most efficiently and trapping it
o Activemdashcollecting solar energy then heating the home with the energy
bull Heat Pumps evaporators condensers amp coolanto Home Heatingmdashdrawing heat from the warm eartho Refrigeratormdashdrawing heat from the warm food and warm airo Air Conditionermdashdrawing heat from the warm room
Electromagnetic Energybull Electricity -- carried in
wiresbull Light -- Each of the colors
of light (ROY G BIV) represents a different amount of electromagnetic energy
bull X-rays amp Cosmic Raysbull TV amp Radio wavesbull Laser light
Nuclear Energybull When the nucleus
splits (Fission) nuclear energy is released in the form of heat energy and light energy
bull Nuclear energy is also released when nuclei collide at high speeds and join (Fusion)
bull MOST CONCENTRATED
Mechanical Energy
bull When work is done to an object it acquires energy The energy it acquires is known as mechanical energy
Mechanical Energy
bull When you kick a football you give mechanical energy to the football to make it move
Energy Conversionbull Energy can be changed from one form to another Changes in the form of energy are called energy conversions
bull Good Examples on Pages 418-419
Energy conversionsbull All forms of energy can be
converted into other formsoThe sunrsquos energy through solar
cells can be converted directly into electricity(Photovoltaic energy)
oGreen plants convert the sunrsquos energy (electromagnetic) into the bonds in starches and sugars (chemical energy) using Photosynthesis
Other energy conversions
oIn an electric motor electromagnetic energy is converted to mechanical energy
oIn a battery chemical energy is converted into electromagnetic energy
oMechanical energy of water falling can be converted to electrical energy in a generator
Hydroelectric Power
Forms of Alternative Energy
Energy Conversions
bull In an automobile engine fuel is burned to convert chemical energy into heat energy The heat energy is then changed into mechanical energy
Chemical Heat Mechanical
The Law of Conservation of Energy
bull Man can neither create nor destroy Energy by ordinary meansoIt can only be converted from one form to another
oIf energy seems to disappear then scientists look for it ndash leading to many important discoveries
Law of Conservation of Energy
bull In 1905 Albert Einstein said that mass and energy can be converted into each other
bull He showed that if matter is destroyed energy is created and if energy is destroyed mass is created
bull E=MC2 bull M=mass C=speed of light
Power = measure of Energybull Work = Force x Distancebull Rate of doing Work orbull Amount of Workunit of timebull Power= WorkTime
bull Power = (Force x Distance)Time
bull Power Units = Watts bull 1Watt=1Joulesec or (1Nmsec)bull 1 Kilowatt = 1000 wattsbull 1 Horsepower = 746 watts
Thermal Energy (Heat) differs from
Temperature
Heat vs Temperaturebull Heat content is the TOTAL
KINETIC ENERGY of the particles in a sample
bull Temperature is the AVERAGE KINETIC ENERGY of the particles in a sample
Which has more Heat and which has the highest temperature
Insulatorsbull There are
thousands of air bubbles trapped in the styrofoam which slows down the heat flow through the layer
Insulation How do the Polar Bears stay warm in
the snow Their dense fine fir traps an air layer next to
their skin
Home Insulationbull The pink fiberglass
fibers trap air in the mat of insulation preventing heat from escaping in the winter or heat from entering during the summer Insulation
Highly Insulating Windows
bull Two or three panes between inside and outside air
bull Insulation is supplied by the Dead Air Space
Image source Southwall Technologies
Heat Transferbull Occurs three waysoConductionoConvectionoRadiation
bull The transfer of heat by direct contact between objects or particles
bull Motion of solid atoms or molecules carried from particle to particle
bull Heat transferred by the movement of molecules within liquid or gaseous substance
bull Warm rises cool sinks
bull A circular motion begins from warmer areas rising due to decreased density moving toward cooler areas which fall because of increased density
bull Wind and Major Weather patterns are caused and move largely because of these convection currents
bull Heat transferred through space
bull MATTER is not needed for radiation
bull EXAMPLE The sunrsquos rays carrying visible light and UV light causing sunburn
Radiationbull Transfer of heat through
electromagnetic radiation (light from stars or light bulbs)
bull Transferred in all directionsbull Matter is not requiredbull Dark or dull objects absorb
more than light or shiny objects do
Temperature
bull Temperature is a measure of the average KE of the particles in a sample of matter
Temperature Conversions
bull oC to oF oF = (95)oC + 32
bull oF to oC oC = 59(oF ndash 32)
bull oC to K K = oC + 273bull K to oC oC = K ndash 273
Going from Celsius to Fahrenheit
Convert 37 oC to oFoF = (95)oC + 32oF = (95)37oC + 32 = 666 + 32 = 986oF
Going from Fahrenheit to CelsiusConvert 68oF to oC
oC = 59(oF ndash 32)oC = 59(68 ndash 32)
= 59(36)
= 20 oC
Going from Kelvin to CelsiusConvert 310 K to oC
oC = K ndash 273oC = 310 ndash 273
= 37oC
Thermal Energybull Which beaker of water has more thermal
energyo B - same temperature but more mass
200 mL
80ordmC
A400 mL
80ordmC
B
Thermal energy relationships a As temperature increases so does
thermal energy (because the kinetic energy of the particles increased)
b Even if the temperature doesnrsquot change the thermal energy in a more massive substance is higher (because it is a total
measure of energy)
c Energy always travels from a high concentration(warm) to a lower concentration(cool) of heat
Land heats up and cools down faster than water The temperature of the water helps keep the
land temperature stable
Thermal Expansionbull Additional heat content causes matter to expandbull Loss of heat content causes matter to contractbull Faster particles take up more space
Sample Problem Thermal Expansion
bull What will be the new volume of 200ml of 20degC water if the temperature is raised to 90degC
bull ∆V = 3σ ∆T Vo
bull = 3 x 69e-6degC x 70degC x 200ml
bull = 2898ml
bull Vnew = Vold + ∆V
bull Vnew = 200ml + 2898ml = 202898ml
Specific heat(CH2O) is the amount of heat required to raise the temperature of 1 kg of a material by one degree (Cdeg or K)
1) C(H2O) = 4184 J kg Cdeg
= 418 kJ kg Cdeg
2) C(sand) = 664 J kg CdegThis is why land heats up quickly during the day and
cools quickly at night and why water takes longer
How to calculate changes in thermal energy
Q = m x Cp x T
Q = quantity of thermal energy
m = mass of substance
T = change in temperature (Tf ndash Ti)
Cp = specific heat of substance(p)
Heat TransferHow much heat is required to warm
230 g of water from 12degC to 90degC
GIVENm = 230 gTi = 12degC
Tf = 90degC
Q = C(H2O)= 4184 JgmiddotoC
WORKQ = mmiddotTmiddotCp
m = 230 gT = 90degC - 12degC = 78degCQ = (230g)(78˚C)(4184 JgmiddotoC)Q = 75061 J
Calorimeters are used to measure the specific heat of a substance
Professional Kingrsquos Ridge
Laws of Thermodynamics
bull First Law Energy is always conservedo Energy added to a system may do two things
bull Increase the total thermal energy of the systembull Do work on the system
o Example Bicycle Pump puts air into tire(work) and heats the air(thermal)
bull Second Law Heat can travel from cold to hot ONLY if work is done on the systemo Example The compressor in a refrigerator
bull Third Law We will never reach Absolute Zero
Uses of Heatbull Heat Engines
o External Combustion Engines Fuel is burned outside of the engine
bull Steam Engine
Internal Combustiono Internal Combustion Engines Fuel is burned inside of the engine
bull Car engines
o 4 stroke engine Pistons are moving up and downbull Intake moving down intake valve open fuel mixture drawn
inbull Compression moving up both valves closedbull Power moving down both valves closed spark igniting fuelbull Exhaust moving up exhaust valve open waste exits
o Cooling system to keep the temperature of the engine within a specific range to prevent damage
o Electrical system Battery is used to start the engine then alternator is used to produce the electricity needed to run the engine and all other systems such as air conditioning
Heating Systemsbull Hot-Water Systemsmdashboilers and radiators -full of hot waterbull Steam Heat Systems-- ldquo -full of hot steambull Electric Heat Systemsmdashproducing heat(lightbulb)bull Forced Air Heating Systemsmdashmost homes todaym burning a fuel
and blowing the warmed air aroundbull Solar Heating using sunlight to heat water and homes
o Passivemdashallowing sunlight to enter home most efficiently and trapping it
o Activemdashcollecting solar energy then heating the home with the energy
bull Heat Pumps evaporators condensers amp coolanto Home Heatingmdashdrawing heat from the warm eartho Refrigeratormdashdrawing heat from the warm food and warm airo Air Conditionermdashdrawing heat from the warm room
Nuclear Energybull When the nucleus
splits (Fission) nuclear energy is released in the form of heat energy and light energy
bull Nuclear energy is also released when nuclei collide at high speeds and join (Fusion)
bull MOST CONCENTRATED
Mechanical Energy
bull When work is done to an object it acquires energy The energy it acquires is known as mechanical energy
Mechanical Energy
bull When you kick a football you give mechanical energy to the football to make it move
Energy Conversionbull Energy can be changed from one form to another Changes in the form of energy are called energy conversions
bull Good Examples on Pages 418-419
Energy conversionsbull All forms of energy can be
converted into other formsoThe sunrsquos energy through solar
cells can be converted directly into electricity(Photovoltaic energy)
oGreen plants convert the sunrsquos energy (electromagnetic) into the bonds in starches and sugars (chemical energy) using Photosynthesis
Other energy conversions
oIn an electric motor electromagnetic energy is converted to mechanical energy
oIn a battery chemical energy is converted into electromagnetic energy
oMechanical energy of water falling can be converted to electrical energy in a generator
Hydroelectric Power
Forms of Alternative Energy
Energy Conversions
bull In an automobile engine fuel is burned to convert chemical energy into heat energy The heat energy is then changed into mechanical energy
Chemical Heat Mechanical
The Law of Conservation of Energy
bull Man can neither create nor destroy Energy by ordinary meansoIt can only be converted from one form to another
oIf energy seems to disappear then scientists look for it ndash leading to many important discoveries
Law of Conservation of Energy
bull In 1905 Albert Einstein said that mass and energy can be converted into each other
bull He showed that if matter is destroyed energy is created and if energy is destroyed mass is created
bull E=MC2 bull M=mass C=speed of light
Power = measure of Energybull Work = Force x Distancebull Rate of doing Work orbull Amount of Workunit of timebull Power= WorkTime
bull Power = (Force x Distance)Time
bull Power Units = Watts bull 1Watt=1Joulesec or (1Nmsec)bull 1 Kilowatt = 1000 wattsbull 1 Horsepower = 746 watts
Thermal Energy (Heat) differs from
Temperature
Heat vs Temperaturebull Heat content is the TOTAL
KINETIC ENERGY of the particles in a sample
bull Temperature is the AVERAGE KINETIC ENERGY of the particles in a sample
Which has more Heat and which has the highest temperature
Insulatorsbull There are
thousands of air bubbles trapped in the styrofoam which slows down the heat flow through the layer
Insulation How do the Polar Bears stay warm in
the snow Their dense fine fir traps an air layer next to
their skin
Home Insulationbull The pink fiberglass
fibers trap air in the mat of insulation preventing heat from escaping in the winter or heat from entering during the summer Insulation
Highly Insulating Windows
bull Two or three panes between inside and outside air
bull Insulation is supplied by the Dead Air Space
Image source Southwall Technologies
Heat Transferbull Occurs three waysoConductionoConvectionoRadiation
bull The transfer of heat by direct contact between objects or particles
bull Motion of solid atoms or molecules carried from particle to particle
bull Heat transferred by the movement of molecules within liquid or gaseous substance
bull Warm rises cool sinks
bull A circular motion begins from warmer areas rising due to decreased density moving toward cooler areas which fall because of increased density
bull Wind and Major Weather patterns are caused and move largely because of these convection currents
bull Heat transferred through space
bull MATTER is not needed for radiation
bull EXAMPLE The sunrsquos rays carrying visible light and UV light causing sunburn
Radiationbull Transfer of heat through
electromagnetic radiation (light from stars or light bulbs)
bull Transferred in all directionsbull Matter is not requiredbull Dark or dull objects absorb
more than light or shiny objects do
Temperature
bull Temperature is a measure of the average KE of the particles in a sample of matter
Temperature Conversions
bull oC to oF oF = (95)oC + 32
bull oF to oC oC = 59(oF ndash 32)
bull oC to K K = oC + 273bull K to oC oC = K ndash 273
Going from Celsius to Fahrenheit
Convert 37 oC to oFoF = (95)oC + 32oF = (95)37oC + 32 = 666 + 32 = 986oF
Going from Fahrenheit to CelsiusConvert 68oF to oC
oC = 59(oF ndash 32)oC = 59(68 ndash 32)
= 59(36)
= 20 oC
Going from Kelvin to CelsiusConvert 310 K to oC
oC = K ndash 273oC = 310 ndash 273
= 37oC
Thermal Energybull Which beaker of water has more thermal
energyo B - same temperature but more mass
200 mL
80ordmC
A400 mL
80ordmC
B
Thermal energy relationships a As temperature increases so does
thermal energy (because the kinetic energy of the particles increased)
b Even if the temperature doesnrsquot change the thermal energy in a more massive substance is higher (because it is a total
measure of energy)
c Energy always travels from a high concentration(warm) to a lower concentration(cool) of heat
Land heats up and cools down faster than water The temperature of the water helps keep the
land temperature stable
Thermal Expansionbull Additional heat content causes matter to expandbull Loss of heat content causes matter to contractbull Faster particles take up more space
Sample Problem Thermal Expansion
bull What will be the new volume of 200ml of 20degC water if the temperature is raised to 90degC
bull ∆V = 3σ ∆T Vo
bull = 3 x 69e-6degC x 70degC x 200ml
bull = 2898ml
bull Vnew = Vold + ∆V
bull Vnew = 200ml + 2898ml = 202898ml
Specific heat(CH2O) is the amount of heat required to raise the temperature of 1 kg of a material by one degree (Cdeg or K)
1) C(H2O) = 4184 J kg Cdeg
= 418 kJ kg Cdeg
2) C(sand) = 664 J kg CdegThis is why land heats up quickly during the day and
cools quickly at night and why water takes longer
How to calculate changes in thermal energy
Q = m x Cp x T
Q = quantity of thermal energy
m = mass of substance
T = change in temperature (Tf ndash Ti)
Cp = specific heat of substance(p)
Heat TransferHow much heat is required to warm
230 g of water from 12degC to 90degC
GIVENm = 230 gTi = 12degC
Tf = 90degC
Q = C(H2O)= 4184 JgmiddotoC
WORKQ = mmiddotTmiddotCp
m = 230 gT = 90degC - 12degC = 78degCQ = (230g)(78˚C)(4184 JgmiddotoC)Q = 75061 J
Calorimeters are used to measure the specific heat of a substance
Professional Kingrsquos Ridge
Laws of Thermodynamics
bull First Law Energy is always conservedo Energy added to a system may do two things
bull Increase the total thermal energy of the systembull Do work on the system
o Example Bicycle Pump puts air into tire(work) and heats the air(thermal)
bull Second Law Heat can travel from cold to hot ONLY if work is done on the systemo Example The compressor in a refrigerator
bull Third Law We will never reach Absolute Zero
Uses of Heatbull Heat Engines
o External Combustion Engines Fuel is burned outside of the engine
bull Steam Engine
Internal Combustiono Internal Combustion Engines Fuel is burned inside of the engine
bull Car engines
o 4 stroke engine Pistons are moving up and downbull Intake moving down intake valve open fuel mixture drawn
inbull Compression moving up both valves closedbull Power moving down both valves closed spark igniting fuelbull Exhaust moving up exhaust valve open waste exits
o Cooling system to keep the temperature of the engine within a specific range to prevent damage
o Electrical system Battery is used to start the engine then alternator is used to produce the electricity needed to run the engine and all other systems such as air conditioning
Heating Systemsbull Hot-Water Systemsmdashboilers and radiators -full of hot waterbull Steam Heat Systems-- ldquo -full of hot steambull Electric Heat Systemsmdashproducing heat(lightbulb)bull Forced Air Heating Systemsmdashmost homes todaym burning a fuel
and blowing the warmed air aroundbull Solar Heating using sunlight to heat water and homes
o Passivemdashallowing sunlight to enter home most efficiently and trapping it
o Activemdashcollecting solar energy then heating the home with the energy
bull Heat Pumps evaporators condensers amp coolanto Home Heatingmdashdrawing heat from the warm eartho Refrigeratormdashdrawing heat from the warm food and warm airo Air Conditionermdashdrawing heat from the warm room
Mechanical Energy
bull When work is done to an object it acquires energy The energy it acquires is known as mechanical energy
Mechanical Energy
bull When you kick a football you give mechanical energy to the football to make it move
Energy Conversionbull Energy can be changed from one form to another Changes in the form of energy are called energy conversions
bull Good Examples on Pages 418-419
Energy conversionsbull All forms of energy can be
converted into other formsoThe sunrsquos energy through solar
cells can be converted directly into electricity(Photovoltaic energy)
oGreen plants convert the sunrsquos energy (electromagnetic) into the bonds in starches and sugars (chemical energy) using Photosynthesis
Other energy conversions
oIn an electric motor electromagnetic energy is converted to mechanical energy
oIn a battery chemical energy is converted into electromagnetic energy
oMechanical energy of water falling can be converted to electrical energy in a generator
Hydroelectric Power
Forms of Alternative Energy
Energy Conversions
bull In an automobile engine fuel is burned to convert chemical energy into heat energy The heat energy is then changed into mechanical energy
Chemical Heat Mechanical
The Law of Conservation of Energy
bull Man can neither create nor destroy Energy by ordinary meansoIt can only be converted from one form to another
oIf energy seems to disappear then scientists look for it ndash leading to many important discoveries
Law of Conservation of Energy
bull In 1905 Albert Einstein said that mass and energy can be converted into each other
bull He showed that if matter is destroyed energy is created and if energy is destroyed mass is created
bull E=MC2 bull M=mass C=speed of light
Power = measure of Energybull Work = Force x Distancebull Rate of doing Work orbull Amount of Workunit of timebull Power= WorkTime
bull Power = (Force x Distance)Time
bull Power Units = Watts bull 1Watt=1Joulesec or (1Nmsec)bull 1 Kilowatt = 1000 wattsbull 1 Horsepower = 746 watts
Thermal Energy (Heat) differs from
Temperature
Heat vs Temperaturebull Heat content is the TOTAL
KINETIC ENERGY of the particles in a sample
bull Temperature is the AVERAGE KINETIC ENERGY of the particles in a sample
Which has more Heat and which has the highest temperature
Insulatorsbull There are
thousands of air bubbles trapped in the styrofoam which slows down the heat flow through the layer
Insulation How do the Polar Bears stay warm in
the snow Their dense fine fir traps an air layer next to
their skin
Home Insulationbull The pink fiberglass
fibers trap air in the mat of insulation preventing heat from escaping in the winter or heat from entering during the summer Insulation
Highly Insulating Windows
bull Two or three panes between inside and outside air
bull Insulation is supplied by the Dead Air Space
Image source Southwall Technologies
Heat Transferbull Occurs three waysoConductionoConvectionoRadiation
bull The transfer of heat by direct contact between objects or particles
bull Motion of solid atoms or molecules carried from particle to particle
bull Heat transferred by the movement of molecules within liquid or gaseous substance
bull Warm rises cool sinks
bull A circular motion begins from warmer areas rising due to decreased density moving toward cooler areas which fall because of increased density
bull Wind and Major Weather patterns are caused and move largely because of these convection currents
bull Heat transferred through space
bull MATTER is not needed for radiation
bull EXAMPLE The sunrsquos rays carrying visible light and UV light causing sunburn
Radiationbull Transfer of heat through
electromagnetic radiation (light from stars or light bulbs)
bull Transferred in all directionsbull Matter is not requiredbull Dark or dull objects absorb
more than light or shiny objects do
Temperature
bull Temperature is a measure of the average KE of the particles in a sample of matter
Temperature Conversions
bull oC to oF oF = (95)oC + 32
bull oF to oC oC = 59(oF ndash 32)
bull oC to K K = oC + 273bull K to oC oC = K ndash 273
Going from Celsius to Fahrenheit
Convert 37 oC to oFoF = (95)oC + 32oF = (95)37oC + 32 = 666 + 32 = 986oF
Going from Fahrenheit to CelsiusConvert 68oF to oC
oC = 59(oF ndash 32)oC = 59(68 ndash 32)
= 59(36)
= 20 oC
Going from Kelvin to CelsiusConvert 310 K to oC
oC = K ndash 273oC = 310 ndash 273
= 37oC
Thermal Energybull Which beaker of water has more thermal
energyo B - same temperature but more mass
200 mL
80ordmC
A400 mL
80ordmC
B
Thermal energy relationships a As temperature increases so does
thermal energy (because the kinetic energy of the particles increased)
b Even if the temperature doesnrsquot change the thermal energy in a more massive substance is higher (because it is a total
measure of energy)
c Energy always travels from a high concentration(warm) to a lower concentration(cool) of heat
Land heats up and cools down faster than water The temperature of the water helps keep the
land temperature stable
Thermal Expansionbull Additional heat content causes matter to expandbull Loss of heat content causes matter to contractbull Faster particles take up more space
Sample Problem Thermal Expansion
bull What will be the new volume of 200ml of 20degC water if the temperature is raised to 90degC
bull ∆V = 3σ ∆T Vo
bull = 3 x 69e-6degC x 70degC x 200ml
bull = 2898ml
bull Vnew = Vold + ∆V
bull Vnew = 200ml + 2898ml = 202898ml
Specific heat(CH2O) is the amount of heat required to raise the temperature of 1 kg of a material by one degree (Cdeg or K)
1) C(H2O) = 4184 J kg Cdeg
= 418 kJ kg Cdeg
2) C(sand) = 664 J kg CdegThis is why land heats up quickly during the day and
cools quickly at night and why water takes longer
How to calculate changes in thermal energy
Q = m x Cp x T
Q = quantity of thermal energy
m = mass of substance
T = change in temperature (Tf ndash Ti)
Cp = specific heat of substance(p)
Heat TransferHow much heat is required to warm
230 g of water from 12degC to 90degC
GIVENm = 230 gTi = 12degC
Tf = 90degC
Q = C(H2O)= 4184 JgmiddotoC
WORKQ = mmiddotTmiddotCp
m = 230 gT = 90degC - 12degC = 78degCQ = (230g)(78˚C)(4184 JgmiddotoC)Q = 75061 J
Calorimeters are used to measure the specific heat of a substance
Professional Kingrsquos Ridge
Laws of Thermodynamics
bull First Law Energy is always conservedo Energy added to a system may do two things
bull Increase the total thermal energy of the systembull Do work on the system
o Example Bicycle Pump puts air into tire(work) and heats the air(thermal)
bull Second Law Heat can travel from cold to hot ONLY if work is done on the systemo Example The compressor in a refrigerator
bull Third Law We will never reach Absolute Zero
Uses of Heatbull Heat Engines
o External Combustion Engines Fuel is burned outside of the engine
bull Steam Engine
Internal Combustiono Internal Combustion Engines Fuel is burned inside of the engine
bull Car engines
o 4 stroke engine Pistons are moving up and downbull Intake moving down intake valve open fuel mixture drawn
inbull Compression moving up both valves closedbull Power moving down both valves closed spark igniting fuelbull Exhaust moving up exhaust valve open waste exits
o Cooling system to keep the temperature of the engine within a specific range to prevent damage
o Electrical system Battery is used to start the engine then alternator is used to produce the electricity needed to run the engine and all other systems such as air conditioning
Heating Systemsbull Hot-Water Systemsmdashboilers and radiators -full of hot waterbull Steam Heat Systems-- ldquo -full of hot steambull Electric Heat Systemsmdashproducing heat(lightbulb)bull Forced Air Heating Systemsmdashmost homes todaym burning a fuel
and blowing the warmed air aroundbull Solar Heating using sunlight to heat water and homes
o Passivemdashallowing sunlight to enter home most efficiently and trapping it
o Activemdashcollecting solar energy then heating the home with the energy
bull Heat Pumps evaporators condensers amp coolanto Home Heatingmdashdrawing heat from the warm eartho Refrigeratormdashdrawing heat from the warm food and warm airo Air Conditionermdashdrawing heat from the warm room
Mechanical Energy
bull When you kick a football you give mechanical energy to the football to make it move
Energy Conversionbull Energy can be changed from one form to another Changes in the form of energy are called energy conversions
bull Good Examples on Pages 418-419
Energy conversionsbull All forms of energy can be
converted into other formsoThe sunrsquos energy through solar
cells can be converted directly into electricity(Photovoltaic energy)
oGreen plants convert the sunrsquos energy (electromagnetic) into the bonds in starches and sugars (chemical energy) using Photosynthesis
Other energy conversions
oIn an electric motor electromagnetic energy is converted to mechanical energy
oIn a battery chemical energy is converted into electromagnetic energy
oMechanical energy of water falling can be converted to electrical energy in a generator
Hydroelectric Power
Forms of Alternative Energy
Energy Conversions
bull In an automobile engine fuel is burned to convert chemical energy into heat energy The heat energy is then changed into mechanical energy
Chemical Heat Mechanical
The Law of Conservation of Energy
bull Man can neither create nor destroy Energy by ordinary meansoIt can only be converted from one form to another
oIf energy seems to disappear then scientists look for it ndash leading to many important discoveries
Law of Conservation of Energy
bull In 1905 Albert Einstein said that mass and energy can be converted into each other
bull He showed that if matter is destroyed energy is created and if energy is destroyed mass is created
bull E=MC2 bull M=mass C=speed of light
Power = measure of Energybull Work = Force x Distancebull Rate of doing Work orbull Amount of Workunit of timebull Power= WorkTime
bull Power = (Force x Distance)Time
bull Power Units = Watts bull 1Watt=1Joulesec or (1Nmsec)bull 1 Kilowatt = 1000 wattsbull 1 Horsepower = 746 watts
Thermal Energy (Heat) differs from
Temperature
Heat vs Temperaturebull Heat content is the TOTAL
KINETIC ENERGY of the particles in a sample
bull Temperature is the AVERAGE KINETIC ENERGY of the particles in a sample
Which has more Heat and which has the highest temperature
Insulatorsbull There are
thousands of air bubbles trapped in the styrofoam which slows down the heat flow through the layer
Insulation How do the Polar Bears stay warm in
the snow Their dense fine fir traps an air layer next to
their skin
Home Insulationbull The pink fiberglass
fibers trap air in the mat of insulation preventing heat from escaping in the winter or heat from entering during the summer Insulation
Highly Insulating Windows
bull Two or three panes between inside and outside air
bull Insulation is supplied by the Dead Air Space
Image source Southwall Technologies
Heat Transferbull Occurs three waysoConductionoConvectionoRadiation
bull The transfer of heat by direct contact between objects or particles
bull Motion of solid atoms or molecules carried from particle to particle
bull Heat transferred by the movement of molecules within liquid or gaseous substance
bull Warm rises cool sinks
bull A circular motion begins from warmer areas rising due to decreased density moving toward cooler areas which fall because of increased density
bull Wind and Major Weather patterns are caused and move largely because of these convection currents
bull Heat transferred through space
bull MATTER is not needed for radiation
bull EXAMPLE The sunrsquos rays carrying visible light and UV light causing sunburn
Radiationbull Transfer of heat through
electromagnetic radiation (light from stars or light bulbs)
bull Transferred in all directionsbull Matter is not requiredbull Dark or dull objects absorb
more than light or shiny objects do
Temperature
bull Temperature is a measure of the average KE of the particles in a sample of matter
Temperature Conversions
bull oC to oF oF = (95)oC + 32
bull oF to oC oC = 59(oF ndash 32)
bull oC to K K = oC + 273bull K to oC oC = K ndash 273
Going from Celsius to Fahrenheit
Convert 37 oC to oFoF = (95)oC + 32oF = (95)37oC + 32 = 666 + 32 = 986oF
Going from Fahrenheit to CelsiusConvert 68oF to oC
oC = 59(oF ndash 32)oC = 59(68 ndash 32)
= 59(36)
= 20 oC
Going from Kelvin to CelsiusConvert 310 K to oC
oC = K ndash 273oC = 310 ndash 273
= 37oC
Thermal Energybull Which beaker of water has more thermal
energyo B - same temperature but more mass
200 mL
80ordmC
A400 mL
80ordmC
B
Thermal energy relationships a As temperature increases so does
thermal energy (because the kinetic energy of the particles increased)
b Even if the temperature doesnrsquot change the thermal energy in a more massive substance is higher (because it is a total
measure of energy)
c Energy always travels from a high concentration(warm) to a lower concentration(cool) of heat
Land heats up and cools down faster than water The temperature of the water helps keep the
land temperature stable
Thermal Expansionbull Additional heat content causes matter to expandbull Loss of heat content causes matter to contractbull Faster particles take up more space
Sample Problem Thermal Expansion
bull What will be the new volume of 200ml of 20degC water if the temperature is raised to 90degC
bull ∆V = 3σ ∆T Vo
bull = 3 x 69e-6degC x 70degC x 200ml
bull = 2898ml
bull Vnew = Vold + ∆V
bull Vnew = 200ml + 2898ml = 202898ml
Specific heat(CH2O) is the amount of heat required to raise the temperature of 1 kg of a material by one degree (Cdeg or K)
1) C(H2O) = 4184 J kg Cdeg
= 418 kJ kg Cdeg
2) C(sand) = 664 J kg CdegThis is why land heats up quickly during the day and
cools quickly at night and why water takes longer
How to calculate changes in thermal energy
Q = m x Cp x T
Q = quantity of thermal energy
m = mass of substance
T = change in temperature (Tf ndash Ti)
Cp = specific heat of substance(p)
Heat TransferHow much heat is required to warm
230 g of water from 12degC to 90degC
GIVENm = 230 gTi = 12degC
Tf = 90degC
Q = C(H2O)= 4184 JgmiddotoC
WORKQ = mmiddotTmiddotCp
m = 230 gT = 90degC - 12degC = 78degCQ = (230g)(78˚C)(4184 JgmiddotoC)Q = 75061 J
Calorimeters are used to measure the specific heat of a substance
Professional Kingrsquos Ridge
Laws of Thermodynamics
bull First Law Energy is always conservedo Energy added to a system may do two things
bull Increase the total thermal energy of the systembull Do work on the system
o Example Bicycle Pump puts air into tire(work) and heats the air(thermal)
bull Second Law Heat can travel from cold to hot ONLY if work is done on the systemo Example The compressor in a refrigerator
bull Third Law We will never reach Absolute Zero
Uses of Heatbull Heat Engines
o External Combustion Engines Fuel is burned outside of the engine
bull Steam Engine
Internal Combustiono Internal Combustion Engines Fuel is burned inside of the engine
bull Car engines
o 4 stroke engine Pistons are moving up and downbull Intake moving down intake valve open fuel mixture drawn
inbull Compression moving up both valves closedbull Power moving down both valves closed spark igniting fuelbull Exhaust moving up exhaust valve open waste exits
o Cooling system to keep the temperature of the engine within a specific range to prevent damage
o Electrical system Battery is used to start the engine then alternator is used to produce the electricity needed to run the engine and all other systems such as air conditioning
Heating Systemsbull Hot-Water Systemsmdashboilers and radiators -full of hot waterbull Steam Heat Systems-- ldquo -full of hot steambull Electric Heat Systemsmdashproducing heat(lightbulb)bull Forced Air Heating Systemsmdashmost homes todaym burning a fuel
and blowing the warmed air aroundbull Solar Heating using sunlight to heat water and homes
o Passivemdashallowing sunlight to enter home most efficiently and trapping it
o Activemdashcollecting solar energy then heating the home with the energy
bull Heat Pumps evaporators condensers amp coolanto Home Heatingmdashdrawing heat from the warm eartho Refrigeratormdashdrawing heat from the warm food and warm airo Air Conditionermdashdrawing heat from the warm room
Energy Conversionbull Energy can be changed from one form to another Changes in the form of energy are called energy conversions
bull Good Examples on Pages 418-419
Energy conversionsbull All forms of energy can be
converted into other formsoThe sunrsquos energy through solar
cells can be converted directly into electricity(Photovoltaic energy)
oGreen plants convert the sunrsquos energy (electromagnetic) into the bonds in starches and sugars (chemical energy) using Photosynthesis
Other energy conversions
oIn an electric motor electromagnetic energy is converted to mechanical energy
oIn a battery chemical energy is converted into electromagnetic energy
oMechanical energy of water falling can be converted to electrical energy in a generator
Hydroelectric Power
Forms of Alternative Energy
Energy Conversions
bull In an automobile engine fuel is burned to convert chemical energy into heat energy The heat energy is then changed into mechanical energy
Chemical Heat Mechanical
The Law of Conservation of Energy
bull Man can neither create nor destroy Energy by ordinary meansoIt can only be converted from one form to another
oIf energy seems to disappear then scientists look for it ndash leading to many important discoveries
Law of Conservation of Energy
bull In 1905 Albert Einstein said that mass and energy can be converted into each other
bull He showed that if matter is destroyed energy is created and if energy is destroyed mass is created
bull E=MC2 bull M=mass C=speed of light
Power = measure of Energybull Work = Force x Distancebull Rate of doing Work orbull Amount of Workunit of timebull Power= WorkTime
bull Power = (Force x Distance)Time
bull Power Units = Watts bull 1Watt=1Joulesec or (1Nmsec)bull 1 Kilowatt = 1000 wattsbull 1 Horsepower = 746 watts
Thermal Energy (Heat) differs from
Temperature
Heat vs Temperaturebull Heat content is the TOTAL
KINETIC ENERGY of the particles in a sample
bull Temperature is the AVERAGE KINETIC ENERGY of the particles in a sample
Which has more Heat and which has the highest temperature
Insulatorsbull There are
thousands of air bubbles trapped in the styrofoam which slows down the heat flow through the layer
Insulation How do the Polar Bears stay warm in
the snow Their dense fine fir traps an air layer next to
their skin
Home Insulationbull The pink fiberglass
fibers trap air in the mat of insulation preventing heat from escaping in the winter or heat from entering during the summer Insulation
Highly Insulating Windows
bull Two or three panes between inside and outside air
bull Insulation is supplied by the Dead Air Space
Image source Southwall Technologies
Heat Transferbull Occurs three waysoConductionoConvectionoRadiation
bull The transfer of heat by direct contact between objects or particles
bull Motion of solid atoms or molecules carried from particle to particle
bull Heat transferred by the movement of molecules within liquid or gaseous substance
bull Warm rises cool sinks
bull A circular motion begins from warmer areas rising due to decreased density moving toward cooler areas which fall because of increased density
bull Wind and Major Weather patterns are caused and move largely because of these convection currents
bull Heat transferred through space
bull MATTER is not needed for radiation
bull EXAMPLE The sunrsquos rays carrying visible light and UV light causing sunburn
Radiationbull Transfer of heat through
electromagnetic radiation (light from stars or light bulbs)
bull Transferred in all directionsbull Matter is not requiredbull Dark or dull objects absorb
more than light or shiny objects do
Temperature
bull Temperature is a measure of the average KE of the particles in a sample of matter
Temperature Conversions
bull oC to oF oF = (95)oC + 32
bull oF to oC oC = 59(oF ndash 32)
bull oC to K K = oC + 273bull K to oC oC = K ndash 273
Going from Celsius to Fahrenheit
Convert 37 oC to oFoF = (95)oC + 32oF = (95)37oC + 32 = 666 + 32 = 986oF
Going from Fahrenheit to CelsiusConvert 68oF to oC
oC = 59(oF ndash 32)oC = 59(68 ndash 32)
= 59(36)
= 20 oC
Going from Kelvin to CelsiusConvert 310 K to oC
oC = K ndash 273oC = 310 ndash 273
= 37oC
Thermal Energybull Which beaker of water has more thermal
energyo B - same temperature but more mass
200 mL
80ordmC
A400 mL
80ordmC
B
Thermal energy relationships a As temperature increases so does
thermal energy (because the kinetic energy of the particles increased)
b Even if the temperature doesnrsquot change the thermal energy in a more massive substance is higher (because it is a total
measure of energy)
c Energy always travels from a high concentration(warm) to a lower concentration(cool) of heat
Land heats up and cools down faster than water The temperature of the water helps keep the
land temperature stable
Thermal Expansionbull Additional heat content causes matter to expandbull Loss of heat content causes matter to contractbull Faster particles take up more space
Sample Problem Thermal Expansion
bull What will be the new volume of 200ml of 20degC water if the temperature is raised to 90degC
bull ∆V = 3σ ∆T Vo
bull = 3 x 69e-6degC x 70degC x 200ml
bull = 2898ml
bull Vnew = Vold + ∆V
bull Vnew = 200ml + 2898ml = 202898ml
Specific heat(CH2O) is the amount of heat required to raise the temperature of 1 kg of a material by one degree (Cdeg or K)
1) C(H2O) = 4184 J kg Cdeg
= 418 kJ kg Cdeg
2) C(sand) = 664 J kg CdegThis is why land heats up quickly during the day and
cools quickly at night and why water takes longer
How to calculate changes in thermal energy
Q = m x Cp x T
Q = quantity of thermal energy
m = mass of substance
T = change in temperature (Tf ndash Ti)
Cp = specific heat of substance(p)
Heat TransferHow much heat is required to warm
230 g of water from 12degC to 90degC
GIVENm = 230 gTi = 12degC
Tf = 90degC
Q = C(H2O)= 4184 JgmiddotoC
WORKQ = mmiddotTmiddotCp
m = 230 gT = 90degC - 12degC = 78degCQ = (230g)(78˚C)(4184 JgmiddotoC)Q = 75061 J
Calorimeters are used to measure the specific heat of a substance
Professional Kingrsquos Ridge
Laws of Thermodynamics
bull First Law Energy is always conservedo Energy added to a system may do two things
bull Increase the total thermal energy of the systembull Do work on the system
o Example Bicycle Pump puts air into tire(work) and heats the air(thermal)
bull Second Law Heat can travel from cold to hot ONLY if work is done on the systemo Example The compressor in a refrigerator
bull Third Law We will never reach Absolute Zero
Uses of Heatbull Heat Engines
o External Combustion Engines Fuel is burned outside of the engine
bull Steam Engine
Internal Combustiono Internal Combustion Engines Fuel is burned inside of the engine
bull Car engines
o 4 stroke engine Pistons are moving up and downbull Intake moving down intake valve open fuel mixture drawn
inbull Compression moving up both valves closedbull Power moving down both valves closed spark igniting fuelbull Exhaust moving up exhaust valve open waste exits
o Cooling system to keep the temperature of the engine within a specific range to prevent damage
o Electrical system Battery is used to start the engine then alternator is used to produce the electricity needed to run the engine and all other systems such as air conditioning
Heating Systemsbull Hot-Water Systemsmdashboilers and radiators -full of hot waterbull Steam Heat Systems-- ldquo -full of hot steambull Electric Heat Systemsmdashproducing heat(lightbulb)bull Forced Air Heating Systemsmdashmost homes todaym burning a fuel
and blowing the warmed air aroundbull Solar Heating using sunlight to heat water and homes
o Passivemdashallowing sunlight to enter home most efficiently and trapping it
o Activemdashcollecting solar energy then heating the home with the energy
bull Heat Pumps evaporators condensers amp coolanto Home Heatingmdashdrawing heat from the warm eartho Refrigeratormdashdrawing heat from the warm food and warm airo Air Conditionermdashdrawing heat from the warm room
Energy conversionsbull All forms of energy can be
converted into other formsoThe sunrsquos energy through solar
cells can be converted directly into electricity(Photovoltaic energy)
oGreen plants convert the sunrsquos energy (electromagnetic) into the bonds in starches and sugars (chemical energy) using Photosynthesis
Other energy conversions
oIn an electric motor electromagnetic energy is converted to mechanical energy
oIn a battery chemical energy is converted into electromagnetic energy
oMechanical energy of water falling can be converted to electrical energy in a generator
Hydroelectric Power
Forms of Alternative Energy
Energy Conversions
bull In an automobile engine fuel is burned to convert chemical energy into heat energy The heat energy is then changed into mechanical energy
Chemical Heat Mechanical
The Law of Conservation of Energy
bull Man can neither create nor destroy Energy by ordinary meansoIt can only be converted from one form to another
oIf energy seems to disappear then scientists look for it ndash leading to many important discoveries
Law of Conservation of Energy
bull In 1905 Albert Einstein said that mass and energy can be converted into each other
bull He showed that if matter is destroyed energy is created and if energy is destroyed mass is created
bull E=MC2 bull M=mass C=speed of light
Power = measure of Energybull Work = Force x Distancebull Rate of doing Work orbull Amount of Workunit of timebull Power= WorkTime
bull Power = (Force x Distance)Time
bull Power Units = Watts bull 1Watt=1Joulesec or (1Nmsec)bull 1 Kilowatt = 1000 wattsbull 1 Horsepower = 746 watts
Thermal Energy (Heat) differs from
Temperature
Heat vs Temperaturebull Heat content is the TOTAL
KINETIC ENERGY of the particles in a sample
bull Temperature is the AVERAGE KINETIC ENERGY of the particles in a sample
Which has more Heat and which has the highest temperature
Insulatorsbull There are
thousands of air bubbles trapped in the styrofoam which slows down the heat flow through the layer
Insulation How do the Polar Bears stay warm in
the snow Their dense fine fir traps an air layer next to
their skin
Home Insulationbull The pink fiberglass
fibers trap air in the mat of insulation preventing heat from escaping in the winter or heat from entering during the summer Insulation
Highly Insulating Windows
bull Two or three panes between inside and outside air
bull Insulation is supplied by the Dead Air Space
Image source Southwall Technologies
Heat Transferbull Occurs three waysoConductionoConvectionoRadiation
bull The transfer of heat by direct contact between objects or particles
bull Motion of solid atoms or molecules carried from particle to particle
bull Heat transferred by the movement of molecules within liquid or gaseous substance
bull Warm rises cool sinks
bull A circular motion begins from warmer areas rising due to decreased density moving toward cooler areas which fall because of increased density
bull Wind and Major Weather patterns are caused and move largely because of these convection currents
bull Heat transferred through space
bull MATTER is not needed for radiation
bull EXAMPLE The sunrsquos rays carrying visible light and UV light causing sunburn
Radiationbull Transfer of heat through
electromagnetic radiation (light from stars or light bulbs)
bull Transferred in all directionsbull Matter is not requiredbull Dark or dull objects absorb
more than light or shiny objects do
Temperature
bull Temperature is a measure of the average KE of the particles in a sample of matter
Temperature Conversions
bull oC to oF oF = (95)oC + 32
bull oF to oC oC = 59(oF ndash 32)
bull oC to K K = oC + 273bull K to oC oC = K ndash 273
Going from Celsius to Fahrenheit
Convert 37 oC to oFoF = (95)oC + 32oF = (95)37oC + 32 = 666 + 32 = 986oF
Going from Fahrenheit to CelsiusConvert 68oF to oC
oC = 59(oF ndash 32)oC = 59(68 ndash 32)
= 59(36)
= 20 oC
Going from Kelvin to CelsiusConvert 310 K to oC
oC = K ndash 273oC = 310 ndash 273
= 37oC
Thermal Energybull Which beaker of water has more thermal
energyo B - same temperature but more mass
200 mL
80ordmC
A400 mL
80ordmC
B
Thermal energy relationships a As temperature increases so does
thermal energy (because the kinetic energy of the particles increased)
b Even if the temperature doesnrsquot change the thermal energy in a more massive substance is higher (because it is a total
measure of energy)
c Energy always travels from a high concentration(warm) to a lower concentration(cool) of heat
Land heats up and cools down faster than water The temperature of the water helps keep the
land temperature stable
Thermal Expansionbull Additional heat content causes matter to expandbull Loss of heat content causes matter to contractbull Faster particles take up more space
Sample Problem Thermal Expansion
bull What will be the new volume of 200ml of 20degC water if the temperature is raised to 90degC
bull ∆V = 3σ ∆T Vo
bull = 3 x 69e-6degC x 70degC x 200ml
bull = 2898ml
bull Vnew = Vold + ∆V
bull Vnew = 200ml + 2898ml = 202898ml
Specific heat(CH2O) is the amount of heat required to raise the temperature of 1 kg of a material by one degree (Cdeg or K)
1) C(H2O) = 4184 J kg Cdeg
= 418 kJ kg Cdeg
2) C(sand) = 664 J kg CdegThis is why land heats up quickly during the day and
cools quickly at night and why water takes longer
How to calculate changes in thermal energy
Q = m x Cp x T
Q = quantity of thermal energy
m = mass of substance
T = change in temperature (Tf ndash Ti)
Cp = specific heat of substance(p)
Heat TransferHow much heat is required to warm
230 g of water from 12degC to 90degC
GIVENm = 230 gTi = 12degC
Tf = 90degC
Q = C(H2O)= 4184 JgmiddotoC
WORKQ = mmiddotTmiddotCp
m = 230 gT = 90degC - 12degC = 78degCQ = (230g)(78˚C)(4184 JgmiddotoC)Q = 75061 J
Calorimeters are used to measure the specific heat of a substance
Professional Kingrsquos Ridge
Laws of Thermodynamics
bull First Law Energy is always conservedo Energy added to a system may do two things
bull Increase the total thermal energy of the systembull Do work on the system
o Example Bicycle Pump puts air into tire(work) and heats the air(thermal)
bull Second Law Heat can travel from cold to hot ONLY if work is done on the systemo Example The compressor in a refrigerator
bull Third Law We will never reach Absolute Zero
Uses of Heatbull Heat Engines
o External Combustion Engines Fuel is burned outside of the engine
bull Steam Engine
Internal Combustiono Internal Combustion Engines Fuel is burned inside of the engine
bull Car engines
o 4 stroke engine Pistons are moving up and downbull Intake moving down intake valve open fuel mixture drawn
inbull Compression moving up both valves closedbull Power moving down both valves closed spark igniting fuelbull Exhaust moving up exhaust valve open waste exits
o Cooling system to keep the temperature of the engine within a specific range to prevent damage
o Electrical system Battery is used to start the engine then alternator is used to produce the electricity needed to run the engine and all other systems such as air conditioning
Heating Systemsbull Hot-Water Systemsmdashboilers and radiators -full of hot waterbull Steam Heat Systems-- ldquo -full of hot steambull Electric Heat Systemsmdashproducing heat(lightbulb)bull Forced Air Heating Systemsmdashmost homes todaym burning a fuel
and blowing the warmed air aroundbull Solar Heating using sunlight to heat water and homes
o Passivemdashallowing sunlight to enter home most efficiently and trapping it
o Activemdashcollecting solar energy then heating the home with the energy
bull Heat Pumps evaporators condensers amp coolanto Home Heatingmdashdrawing heat from the warm eartho Refrigeratormdashdrawing heat from the warm food and warm airo Air Conditionermdashdrawing heat from the warm room
Other energy conversions
oIn an electric motor electromagnetic energy is converted to mechanical energy
oIn a battery chemical energy is converted into electromagnetic energy
oMechanical energy of water falling can be converted to electrical energy in a generator
Hydroelectric Power
Forms of Alternative Energy
Energy Conversions
bull In an automobile engine fuel is burned to convert chemical energy into heat energy The heat energy is then changed into mechanical energy
Chemical Heat Mechanical
The Law of Conservation of Energy
bull Man can neither create nor destroy Energy by ordinary meansoIt can only be converted from one form to another
oIf energy seems to disappear then scientists look for it ndash leading to many important discoveries
Law of Conservation of Energy
bull In 1905 Albert Einstein said that mass and energy can be converted into each other
bull He showed that if matter is destroyed energy is created and if energy is destroyed mass is created
bull E=MC2 bull M=mass C=speed of light
Power = measure of Energybull Work = Force x Distancebull Rate of doing Work orbull Amount of Workunit of timebull Power= WorkTime
bull Power = (Force x Distance)Time
bull Power Units = Watts bull 1Watt=1Joulesec or (1Nmsec)bull 1 Kilowatt = 1000 wattsbull 1 Horsepower = 746 watts
Thermal Energy (Heat) differs from
Temperature
Heat vs Temperaturebull Heat content is the TOTAL
KINETIC ENERGY of the particles in a sample
bull Temperature is the AVERAGE KINETIC ENERGY of the particles in a sample
Which has more Heat and which has the highest temperature
Insulatorsbull There are
thousands of air bubbles trapped in the styrofoam which slows down the heat flow through the layer
Insulation How do the Polar Bears stay warm in
the snow Their dense fine fir traps an air layer next to
their skin
Home Insulationbull The pink fiberglass
fibers trap air in the mat of insulation preventing heat from escaping in the winter or heat from entering during the summer Insulation
Highly Insulating Windows
bull Two or three panes between inside and outside air
bull Insulation is supplied by the Dead Air Space
Image source Southwall Technologies
Heat Transferbull Occurs three waysoConductionoConvectionoRadiation
bull The transfer of heat by direct contact between objects or particles
bull Motion of solid atoms or molecules carried from particle to particle
bull Heat transferred by the movement of molecules within liquid or gaseous substance
bull Warm rises cool sinks
bull A circular motion begins from warmer areas rising due to decreased density moving toward cooler areas which fall because of increased density
bull Wind and Major Weather patterns are caused and move largely because of these convection currents
bull Heat transferred through space
bull MATTER is not needed for radiation
bull EXAMPLE The sunrsquos rays carrying visible light and UV light causing sunburn
Radiationbull Transfer of heat through
electromagnetic radiation (light from stars or light bulbs)
bull Transferred in all directionsbull Matter is not requiredbull Dark or dull objects absorb
more than light or shiny objects do
Temperature
bull Temperature is a measure of the average KE of the particles in a sample of matter
Temperature Conversions
bull oC to oF oF = (95)oC + 32
bull oF to oC oC = 59(oF ndash 32)
bull oC to K K = oC + 273bull K to oC oC = K ndash 273
Going from Celsius to Fahrenheit
Convert 37 oC to oFoF = (95)oC + 32oF = (95)37oC + 32 = 666 + 32 = 986oF
Going from Fahrenheit to CelsiusConvert 68oF to oC
oC = 59(oF ndash 32)oC = 59(68 ndash 32)
= 59(36)
= 20 oC
Going from Kelvin to CelsiusConvert 310 K to oC
oC = K ndash 273oC = 310 ndash 273
= 37oC
Thermal Energybull Which beaker of water has more thermal
energyo B - same temperature but more mass
200 mL
80ordmC
A400 mL
80ordmC
B
Thermal energy relationships a As temperature increases so does
thermal energy (because the kinetic energy of the particles increased)
b Even if the temperature doesnrsquot change the thermal energy in a more massive substance is higher (because it is a total
measure of energy)
c Energy always travels from a high concentration(warm) to a lower concentration(cool) of heat
Land heats up and cools down faster than water The temperature of the water helps keep the
land temperature stable
Thermal Expansionbull Additional heat content causes matter to expandbull Loss of heat content causes matter to contractbull Faster particles take up more space
Sample Problem Thermal Expansion
bull What will be the new volume of 200ml of 20degC water if the temperature is raised to 90degC
bull ∆V = 3σ ∆T Vo
bull = 3 x 69e-6degC x 70degC x 200ml
bull = 2898ml
bull Vnew = Vold + ∆V
bull Vnew = 200ml + 2898ml = 202898ml
Specific heat(CH2O) is the amount of heat required to raise the temperature of 1 kg of a material by one degree (Cdeg or K)
1) C(H2O) = 4184 J kg Cdeg
= 418 kJ kg Cdeg
2) C(sand) = 664 J kg CdegThis is why land heats up quickly during the day and
cools quickly at night and why water takes longer
How to calculate changes in thermal energy
Q = m x Cp x T
Q = quantity of thermal energy
m = mass of substance
T = change in temperature (Tf ndash Ti)
Cp = specific heat of substance(p)
Heat TransferHow much heat is required to warm
230 g of water from 12degC to 90degC
GIVENm = 230 gTi = 12degC
Tf = 90degC
Q = C(H2O)= 4184 JgmiddotoC
WORKQ = mmiddotTmiddotCp
m = 230 gT = 90degC - 12degC = 78degCQ = (230g)(78˚C)(4184 JgmiddotoC)Q = 75061 J
Calorimeters are used to measure the specific heat of a substance
Professional Kingrsquos Ridge
Laws of Thermodynamics
bull First Law Energy is always conservedo Energy added to a system may do two things
bull Increase the total thermal energy of the systembull Do work on the system
o Example Bicycle Pump puts air into tire(work) and heats the air(thermal)
bull Second Law Heat can travel from cold to hot ONLY if work is done on the systemo Example The compressor in a refrigerator
bull Third Law We will never reach Absolute Zero
Uses of Heatbull Heat Engines
o External Combustion Engines Fuel is burned outside of the engine
bull Steam Engine
Internal Combustiono Internal Combustion Engines Fuel is burned inside of the engine
bull Car engines
o 4 stroke engine Pistons are moving up and downbull Intake moving down intake valve open fuel mixture drawn
inbull Compression moving up both valves closedbull Power moving down both valves closed spark igniting fuelbull Exhaust moving up exhaust valve open waste exits
o Cooling system to keep the temperature of the engine within a specific range to prevent damage
o Electrical system Battery is used to start the engine then alternator is used to produce the electricity needed to run the engine and all other systems such as air conditioning
Heating Systemsbull Hot-Water Systemsmdashboilers and radiators -full of hot waterbull Steam Heat Systems-- ldquo -full of hot steambull Electric Heat Systemsmdashproducing heat(lightbulb)bull Forced Air Heating Systemsmdashmost homes todaym burning a fuel
and blowing the warmed air aroundbull Solar Heating using sunlight to heat water and homes
o Passivemdashallowing sunlight to enter home most efficiently and trapping it
o Activemdashcollecting solar energy then heating the home with the energy
bull Heat Pumps evaporators condensers amp coolanto Home Heatingmdashdrawing heat from the warm eartho Refrigeratormdashdrawing heat from the warm food and warm airo Air Conditionermdashdrawing heat from the warm room
Hydroelectric Power
Forms of Alternative Energy
Energy Conversions
bull In an automobile engine fuel is burned to convert chemical energy into heat energy The heat energy is then changed into mechanical energy
Chemical Heat Mechanical
The Law of Conservation of Energy
bull Man can neither create nor destroy Energy by ordinary meansoIt can only be converted from one form to another
oIf energy seems to disappear then scientists look for it ndash leading to many important discoveries
Law of Conservation of Energy
bull In 1905 Albert Einstein said that mass and energy can be converted into each other
bull He showed that if matter is destroyed energy is created and if energy is destroyed mass is created
bull E=MC2 bull M=mass C=speed of light
Power = measure of Energybull Work = Force x Distancebull Rate of doing Work orbull Amount of Workunit of timebull Power= WorkTime
bull Power = (Force x Distance)Time
bull Power Units = Watts bull 1Watt=1Joulesec or (1Nmsec)bull 1 Kilowatt = 1000 wattsbull 1 Horsepower = 746 watts
Thermal Energy (Heat) differs from
Temperature
Heat vs Temperaturebull Heat content is the TOTAL
KINETIC ENERGY of the particles in a sample
bull Temperature is the AVERAGE KINETIC ENERGY of the particles in a sample
Which has more Heat and which has the highest temperature
Insulatorsbull There are
thousands of air bubbles trapped in the styrofoam which slows down the heat flow through the layer
Insulation How do the Polar Bears stay warm in
the snow Their dense fine fir traps an air layer next to
their skin
Home Insulationbull The pink fiberglass
fibers trap air in the mat of insulation preventing heat from escaping in the winter or heat from entering during the summer Insulation
Highly Insulating Windows
bull Two or three panes between inside and outside air
bull Insulation is supplied by the Dead Air Space
Image source Southwall Technologies
Heat Transferbull Occurs three waysoConductionoConvectionoRadiation
bull The transfer of heat by direct contact between objects or particles
bull Motion of solid atoms or molecules carried from particle to particle
bull Heat transferred by the movement of molecules within liquid or gaseous substance
bull Warm rises cool sinks
bull A circular motion begins from warmer areas rising due to decreased density moving toward cooler areas which fall because of increased density
bull Wind and Major Weather patterns are caused and move largely because of these convection currents
bull Heat transferred through space
bull MATTER is not needed for radiation
bull EXAMPLE The sunrsquos rays carrying visible light and UV light causing sunburn
Radiationbull Transfer of heat through
electromagnetic radiation (light from stars or light bulbs)
bull Transferred in all directionsbull Matter is not requiredbull Dark or dull objects absorb
more than light or shiny objects do
Temperature
bull Temperature is a measure of the average KE of the particles in a sample of matter
Temperature Conversions
bull oC to oF oF = (95)oC + 32
bull oF to oC oC = 59(oF ndash 32)
bull oC to K K = oC + 273bull K to oC oC = K ndash 273
Going from Celsius to Fahrenheit
Convert 37 oC to oFoF = (95)oC + 32oF = (95)37oC + 32 = 666 + 32 = 986oF
Going from Fahrenheit to CelsiusConvert 68oF to oC
oC = 59(oF ndash 32)oC = 59(68 ndash 32)
= 59(36)
= 20 oC
Going from Kelvin to CelsiusConvert 310 K to oC
oC = K ndash 273oC = 310 ndash 273
= 37oC
Thermal Energybull Which beaker of water has more thermal
energyo B - same temperature but more mass
200 mL
80ordmC
A400 mL
80ordmC
B
Thermal energy relationships a As temperature increases so does
thermal energy (because the kinetic energy of the particles increased)
b Even if the temperature doesnrsquot change the thermal energy in a more massive substance is higher (because it is a total
measure of energy)
c Energy always travels from a high concentration(warm) to a lower concentration(cool) of heat
Land heats up and cools down faster than water The temperature of the water helps keep the
land temperature stable
Thermal Expansionbull Additional heat content causes matter to expandbull Loss of heat content causes matter to contractbull Faster particles take up more space
Sample Problem Thermal Expansion
bull What will be the new volume of 200ml of 20degC water if the temperature is raised to 90degC
bull ∆V = 3σ ∆T Vo
bull = 3 x 69e-6degC x 70degC x 200ml
bull = 2898ml
bull Vnew = Vold + ∆V
bull Vnew = 200ml + 2898ml = 202898ml
Specific heat(CH2O) is the amount of heat required to raise the temperature of 1 kg of a material by one degree (Cdeg or K)
1) C(H2O) = 4184 J kg Cdeg
= 418 kJ kg Cdeg
2) C(sand) = 664 J kg CdegThis is why land heats up quickly during the day and
cools quickly at night and why water takes longer
How to calculate changes in thermal energy
Q = m x Cp x T
Q = quantity of thermal energy
m = mass of substance
T = change in temperature (Tf ndash Ti)
Cp = specific heat of substance(p)
Heat TransferHow much heat is required to warm
230 g of water from 12degC to 90degC
GIVENm = 230 gTi = 12degC
Tf = 90degC
Q = C(H2O)= 4184 JgmiddotoC
WORKQ = mmiddotTmiddotCp
m = 230 gT = 90degC - 12degC = 78degCQ = (230g)(78˚C)(4184 JgmiddotoC)Q = 75061 J
Calorimeters are used to measure the specific heat of a substance
Professional Kingrsquos Ridge
Laws of Thermodynamics
bull First Law Energy is always conservedo Energy added to a system may do two things
bull Increase the total thermal energy of the systembull Do work on the system
o Example Bicycle Pump puts air into tire(work) and heats the air(thermal)
bull Second Law Heat can travel from cold to hot ONLY if work is done on the systemo Example The compressor in a refrigerator
bull Third Law We will never reach Absolute Zero
Uses of Heatbull Heat Engines
o External Combustion Engines Fuel is burned outside of the engine
bull Steam Engine
Internal Combustiono Internal Combustion Engines Fuel is burned inside of the engine
bull Car engines
o 4 stroke engine Pistons are moving up and downbull Intake moving down intake valve open fuel mixture drawn
inbull Compression moving up both valves closedbull Power moving down both valves closed spark igniting fuelbull Exhaust moving up exhaust valve open waste exits
o Cooling system to keep the temperature of the engine within a specific range to prevent damage
o Electrical system Battery is used to start the engine then alternator is used to produce the electricity needed to run the engine and all other systems such as air conditioning
Heating Systemsbull Hot-Water Systemsmdashboilers and radiators -full of hot waterbull Steam Heat Systems-- ldquo -full of hot steambull Electric Heat Systemsmdashproducing heat(lightbulb)bull Forced Air Heating Systemsmdashmost homes todaym burning a fuel
and blowing the warmed air aroundbull Solar Heating using sunlight to heat water and homes
o Passivemdashallowing sunlight to enter home most efficiently and trapping it
o Activemdashcollecting solar energy then heating the home with the energy
bull Heat Pumps evaporators condensers amp coolanto Home Heatingmdashdrawing heat from the warm eartho Refrigeratormdashdrawing heat from the warm food and warm airo Air Conditionermdashdrawing heat from the warm room
Forms of Alternative Energy
Energy Conversions
bull In an automobile engine fuel is burned to convert chemical energy into heat energy The heat energy is then changed into mechanical energy
Chemical Heat Mechanical
The Law of Conservation of Energy
bull Man can neither create nor destroy Energy by ordinary meansoIt can only be converted from one form to another
oIf energy seems to disappear then scientists look for it ndash leading to many important discoveries
Law of Conservation of Energy
bull In 1905 Albert Einstein said that mass and energy can be converted into each other
bull He showed that if matter is destroyed energy is created and if energy is destroyed mass is created
bull E=MC2 bull M=mass C=speed of light
Power = measure of Energybull Work = Force x Distancebull Rate of doing Work orbull Amount of Workunit of timebull Power= WorkTime
bull Power = (Force x Distance)Time
bull Power Units = Watts bull 1Watt=1Joulesec or (1Nmsec)bull 1 Kilowatt = 1000 wattsbull 1 Horsepower = 746 watts
Thermal Energy (Heat) differs from
Temperature
Heat vs Temperaturebull Heat content is the TOTAL
KINETIC ENERGY of the particles in a sample
bull Temperature is the AVERAGE KINETIC ENERGY of the particles in a sample
Which has more Heat and which has the highest temperature
Insulatorsbull There are
thousands of air bubbles trapped in the styrofoam which slows down the heat flow through the layer
Insulation How do the Polar Bears stay warm in
the snow Their dense fine fir traps an air layer next to
their skin
Home Insulationbull The pink fiberglass
fibers trap air in the mat of insulation preventing heat from escaping in the winter or heat from entering during the summer Insulation
Highly Insulating Windows
bull Two or three panes between inside and outside air
bull Insulation is supplied by the Dead Air Space
Image source Southwall Technologies
Heat Transferbull Occurs three waysoConductionoConvectionoRadiation
bull The transfer of heat by direct contact between objects or particles
bull Motion of solid atoms or molecules carried from particle to particle
bull Heat transferred by the movement of molecules within liquid or gaseous substance
bull Warm rises cool sinks
bull A circular motion begins from warmer areas rising due to decreased density moving toward cooler areas which fall because of increased density
bull Wind and Major Weather patterns are caused and move largely because of these convection currents
bull Heat transferred through space
bull MATTER is not needed for radiation
bull EXAMPLE The sunrsquos rays carrying visible light and UV light causing sunburn
Radiationbull Transfer of heat through
electromagnetic radiation (light from stars or light bulbs)
bull Transferred in all directionsbull Matter is not requiredbull Dark or dull objects absorb
more than light or shiny objects do
Temperature
bull Temperature is a measure of the average KE of the particles in a sample of matter
Temperature Conversions
bull oC to oF oF = (95)oC + 32
bull oF to oC oC = 59(oF ndash 32)
bull oC to K K = oC + 273bull K to oC oC = K ndash 273
Going from Celsius to Fahrenheit
Convert 37 oC to oFoF = (95)oC + 32oF = (95)37oC + 32 = 666 + 32 = 986oF
Going from Fahrenheit to CelsiusConvert 68oF to oC
oC = 59(oF ndash 32)oC = 59(68 ndash 32)
= 59(36)
= 20 oC
Going from Kelvin to CelsiusConvert 310 K to oC
oC = K ndash 273oC = 310 ndash 273
= 37oC
Thermal Energybull Which beaker of water has more thermal
energyo B - same temperature but more mass
200 mL
80ordmC
A400 mL
80ordmC
B
Thermal energy relationships a As temperature increases so does
thermal energy (because the kinetic energy of the particles increased)
b Even if the temperature doesnrsquot change the thermal energy in a more massive substance is higher (because it is a total
measure of energy)
c Energy always travels from a high concentration(warm) to a lower concentration(cool) of heat
Land heats up and cools down faster than water The temperature of the water helps keep the
land temperature stable
Thermal Expansionbull Additional heat content causes matter to expandbull Loss of heat content causes matter to contractbull Faster particles take up more space
Sample Problem Thermal Expansion
bull What will be the new volume of 200ml of 20degC water if the temperature is raised to 90degC
bull ∆V = 3σ ∆T Vo
bull = 3 x 69e-6degC x 70degC x 200ml
bull = 2898ml
bull Vnew = Vold + ∆V
bull Vnew = 200ml + 2898ml = 202898ml
Specific heat(CH2O) is the amount of heat required to raise the temperature of 1 kg of a material by one degree (Cdeg or K)
1) C(H2O) = 4184 J kg Cdeg
= 418 kJ kg Cdeg
2) C(sand) = 664 J kg CdegThis is why land heats up quickly during the day and
cools quickly at night and why water takes longer
How to calculate changes in thermal energy
Q = m x Cp x T
Q = quantity of thermal energy
m = mass of substance
T = change in temperature (Tf ndash Ti)
Cp = specific heat of substance(p)
Heat TransferHow much heat is required to warm
230 g of water from 12degC to 90degC
GIVENm = 230 gTi = 12degC
Tf = 90degC
Q = C(H2O)= 4184 JgmiddotoC
WORKQ = mmiddotTmiddotCp
m = 230 gT = 90degC - 12degC = 78degCQ = (230g)(78˚C)(4184 JgmiddotoC)Q = 75061 J
Calorimeters are used to measure the specific heat of a substance
Professional Kingrsquos Ridge
Laws of Thermodynamics
bull First Law Energy is always conservedo Energy added to a system may do two things
bull Increase the total thermal energy of the systembull Do work on the system
o Example Bicycle Pump puts air into tire(work) and heats the air(thermal)
bull Second Law Heat can travel from cold to hot ONLY if work is done on the systemo Example The compressor in a refrigerator
bull Third Law We will never reach Absolute Zero
Uses of Heatbull Heat Engines
o External Combustion Engines Fuel is burned outside of the engine
bull Steam Engine
Internal Combustiono Internal Combustion Engines Fuel is burned inside of the engine
bull Car engines
o 4 stroke engine Pistons are moving up and downbull Intake moving down intake valve open fuel mixture drawn
inbull Compression moving up both valves closedbull Power moving down both valves closed spark igniting fuelbull Exhaust moving up exhaust valve open waste exits
o Cooling system to keep the temperature of the engine within a specific range to prevent damage
o Electrical system Battery is used to start the engine then alternator is used to produce the electricity needed to run the engine and all other systems such as air conditioning
Heating Systemsbull Hot-Water Systemsmdashboilers and radiators -full of hot waterbull Steam Heat Systems-- ldquo -full of hot steambull Electric Heat Systemsmdashproducing heat(lightbulb)bull Forced Air Heating Systemsmdashmost homes todaym burning a fuel
and blowing the warmed air aroundbull Solar Heating using sunlight to heat water and homes
o Passivemdashallowing sunlight to enter home most efficiently and trapping it
o Activemdashcollecting solar energy then heating the home with the energy
bull Heat Pumps evaporators condensers amp coolanto Home Heatingmdashdrawing heat from the warm eartho Refrigeratormdashdrawing heat from the warm food and warm airo Air Conditionermdashdrawing heat from the warm room
Energy Conversions
bull In an automobile engine fuel is burned to convert chemical energy into heat energy The heat energy is then changed into mechanical energy
Chemical Heat Mechanical
The Law of Conservation of Energy
bull Man can neither create nor destroy Energy by ordinary meansoIt can only be converted from one form to another
oIf energy seems to disappear then scientists look for it ndash leading to many important discoveries
Law of Conservation of Energy
bull In 1905 Albert Einstein said that mass and energy can be converted into each other
bull He showed that if matter is destroyed energy is created and if energy is destroyed mass is created
bull E=MC2 bull M=mass C=speed of light
Power = measure of Energybull Work = Force x Distancebull Rate of doing Work orbull Amount of Workunit of timebull Power= WorkTime
bull Power = (Force x Distance)Time
bull Power Units = Watts bull 1Watt=1Joulesec or (1Nmsec)bull 1 Kilowatt = 1000 wattsbull 1 Horsepower = 746 watts
Thermal Energy (Heat) differs from
Temperature
Heat vs Temperaturebull Heat content is the TOTAL
KINETIC ENERGY of the particles in a sample
bull Temperature is the AVERAGE KINETIC ENERGY of the particles in a sample
Which has more Heat and which has the highest temperature
Insulatorsbull There are
thousands of air bubbles trapped in the styrofoam which slows down the heat flow through the layer
Insulation How do the Polar Bears stay warm in
the snow Their dense fine fir traps an air layer next to
their skin
Home Insulationbull The pink fiberglass
fibers trap air in the mat of insulation preventing heat from escaping in the winter or heat from entering during the summer Insulation
Highly Insulating Windows
bull Two or three panes between inside and outside air
bull Insulation is supplied by the Dead Air Space
Image source Southwall Technologies
Heat Transferbull Occurs three waysoConductionoConvectionoRadiation
bull The transfer of heat by direct contact between objects or particles
bull Motion of solid atoms or molecules carried from particle to particle
bull Heat transferred by the movement of molecules within liquid or gaseous substance
bull Warm rises cool sinks
bull A circular motion begins from warmer areas rising due to decreased density moving toward cooler areas which fall because of increased density
bull Wind and Major Weather patterns are caused and move largely because of these convection currents
bull Heat transferred through space
bull MATTER is not needed for radiation
bull EXAMPLE The sunrsquos rays carrying visible light and UV light causing sunburn
Radiationbull Transfer of heat through
electromagnetic radiation (light from stars or light bulbs)
bull Transferred in all directionsbull Matter is not requiredbull Dark or dull objects absorb
more than light or shiny objects do
Temperature
bull Temperature is a measure of the average KE of the particles in a sample of matter
Temperature Conversions
bull oC to oF oF = (95)oC + 32
bull oF to oC oC = 59(oF ndash 32)
bull oC to K K = oC + 273bull K to oC oC = K ndash 273
Going from Celsius to Fahrenheit
Convert 37 oC to oFoF = (95)oC + 32oF = (95)37oC + 32 = 666 + 32 = 986oF
Going from Fahrenheit to CelsiusConvert 68oF to oC
oC = 59(oF ndash 32)oC = 59(68 ndash 32)
= 59(36)
= 20 oC
Going from Kelvin to CelsiusConvert 310 K to oC
oC = K ndash 273oC = 310 ndash 273
= 37oC
Thermal Energybull Which beaker of water has more thermal
energyo B - same temperature but more mass
200 mL
80ordmC
A400 mL
80ordmC
B
Thermal energy relationships a As temperature increases so does
thermal energy (because the kinetic energy of the particles increased)
b Even if the temperature doesnrsquot change the thermal energy in a more massive substance is higher (because it is a total
measure of energy)
c Energy always travels from a high concentration(warm) to a lower concentration(cool) of heat
Land heats up and cools down faster than water The temperature of the water helps keep the
land temperature stable
Thermal Expansionbull Additional heat content causes matter to expandbull Loss of heat content causes matter to contractbull Faster particles take up more space
Sample Problem Thermal Expansion
bull What will be the new volume of 200ml of 20degC water if the temperature is raised to 90degC
bull ∆V = 3σ ∆T Vo
bull = 3 x 69e-6degC x 70degC x 200ml
bull = 2898ml
bull Vnew = Vold + ∆V
bull Vnew = 200ml + 2898ml = 202898ml
Specific heat(CH2O) is the amount of heat required to raise the temperature of 1 kg of a material by one degree (Cdeg or K)
1) C(H2O) = 4184 J kg Cdeg
= 418 kJ kg Cdeg
2) C(sand) = 664 J kg CdegThis is why land heats up quickly during the day and
cools quickly at night and why water takes longer
How to calculate changes in thermal energy
Q = m x Cp x T
Q = quantity of thermal energy
m = mass of substance
T = change in temperature (Tf ndash Ti)
Cp = specific heat of substance(p)
Heat TransferHow much heat is required to warm
230 g of water from 12degC to 90degC
GIVENm = 230 gTi = 12degC
Tf = 90degC
Q = C(H2O)= 4184 JgmiddotoC
WORKQ = mmiddotTmiddotCp
m = 230 gT = 90degC - 12degC = 78degCQ = (230g)(78˚C)(4184 JgmiddotoC)Q = 75061 J
Calorimeters are used to measure the specific heat of a substance
Professional Kingrsquos Ridge
Laws of Thermodynamics
bull First Law Energy is always conservedo Energy added to a system may do two things
bull Increase the total thermal energy of the systembull Do work on the system
o Example Bicycle Pump puts air into tire(work) and heats the air(thermal)
bull Second Law Heat can travel from cold to hot ONLY if work is done on the systemo Example The compressor in a refrigerator
bull Third Law We will never reach Absolute Zero
Uses of Heatbull Heat Engines
o External Combustion Engines Fuel is burned outside of the engine
bull Steam Engine
Internal Combustiono Internal Combustion Engines Fuel is burned inside of the engine
bull Car engines
o 4 stroke engine Pistons are moving up and downbull Intake moving down intake valve open fuel mixture drawn
inbull Compression moving up both valves closedbull Power moving down both valves closed spark igniting fuelbull Exhaust moving up exhaust valve open waste exits
o Cooling system to keep the temperature of the engine within a specific range to prevent damage
o Electrical system Battery is used to start the engine then alternator is used to produce the electricity needed to run the engine and all other systems such as air conditioning
Heating Systemsbull Hot-Water Systemsmdashboilers and radiators -full of hot waterbull Steam Heat Systems-- ldquo -full of hot steambull Electric Heat Systemsmdashproducing heat(lightbulb)bull Forced Air Heating Systemsmdashmost homes todaym burning a fuel
and blowing the warmed air aroundbull Solar Heating using sunlight to heat water and homes
o Passivemdashallowing sunlight to enter home most efficiently and trapping it
o Activemdashcollecting solar energy then heating the home with the energy
bull Heat Pumps evaporators condensers amp coolanto Home Heatingmdashdrawing heat from the warm eartho Refrigeratormdashdrawing heat from the warm food and warm airo Air Conditionermdashdrawing heat from the warm room
Chemical Heat Mechanical
The Law of Conservation of Energy
bull Man can neither create nor destroy Energy by ordinary meansoIt can only be converted from one form to another
oIf energy seems to disappear then scientists look for it ndash leading to many important discoveries
Law of Conservation of Energy
bull In 1905 Albert Einstein said that mass and energy can be converted into each other
bull He showed that if matter is destroyed energy is created and if energy is destroyed mass is created
bull E=MC2 bull M=mass C=speed of light
Power = measure of Energybull Work = Force x Distancebull Rate of doing Work orbull Amount of Workunit of timebull Power= WorkTime
bull Power = (Force x Distance)Time
bull Power Units = Watts bull 1Watt=1Joulesec or (1Nmsec)bull 1 Kilowatt = 1000 wattsbull 1 Horsepower = 746 watts
Thermal Energy (Heat) differs from
Temperature
Heat vs Temperaturebull Heat content is the TOTAL
KINETIC ENERGY of the particles in a sample
bull Temperature is the AVERAGE KINETIC ENERGY of the particles in a sample
Which has more Heat and which has the highest temperature
Insulatorsbull There are
thousands of air bubbles trapped in the styrofoam which slows down the heat flow through the layer
Insulation How do the Polar Bears stay warm in
the snow Their dense fine fir traps an air layer next to
their skin
Home Insulationbull The pink fiberglass
fibers trap air in the mat of insulation preventing heat from escaping in the winter or heat from entering during the summer Insulation
Highly Insulating Windows
bull Two or three panes between inside and outside air
bull Insulation is supplied by the Dead Air Space
Image source Southwall Technologies
Heat Transferbull Occurs three waysoConductionoConvectionoRadiation
bull The transfer of heat by direct contact between objects or particles
bull Motion of solid atoms or molecules carried from particle to particle
bull Heat transferred by the movement of molecules within liquid or gaseous substance
bull Warm rises cool sinks
bull A circular motion begins from warmer areas rising due to decreased density moving toward cooler areas which fall because of increased density
bull Wind and Major Weather patterns are caused and move largely because of these convection currents
bull Heat transferred through space
bull MATTER is not needed for radiation
bull EXAMPLE The sunrsquos rays carrying visible light and UV light causing sunburn
Radiationbull Transfer of heat through
electromagnetic radiation (light from stars or light bulbs)
bull Transferred in all directionsbull Matter is not requiredbull Dark or dull objects absorb
more than light or shiny objects do
Temperature
bull Temperature is a measure of the average KE of the particles in a sample of matter
Temperature Conversions
bull oC to oF oF = (95)oC + 32
bull oF to oC oC = 59(oF ndash 32)
bull oC to K K = oC + 273bull K to oC oC = K ndash 273
Going from Celsius to Fahrenheit
Convert 37 oC to oFoF = (95)oC + 32oF = (95)37oC + 32 = 666 + 32 = 986oF
Going from Fahrenheit to CelsiusConvert 68oF to oC
oC = 59(oF ndash 32)oC = 59(68 ndash 32)
= 59(36)
= 20 oC
Going from Kelvin to CelsiusConvert 310 K to oC
oC = K ndash 273oC = 310 ndash 273
= 37oC
Thermal Energybull Which beaker of water has more thermal
energyo B - same temperature but more mass
200 mL
80ordmC
A400 mL
80ordmC
B
Thermal energy relationships a As temperature increases so does
thermal energy (because the kinetic energy of the particles increased)
b Even if the temperature doesnrsquot change the thermal energy in a more massive substance is higher (because it is a total
measure of energy)
c Energy always travels from a high concentration(warm) to a lower concentration(cool) of heat
Land heats up and cools down faster than water The temperature of the water helps keep the
land temperature stable
Thermal Expansionbull Additional heat content causes matter to expandbull Loss of heat content causes matter to contractbull Faster particles take up more space
Sample Problem Thermal Expansion
bull What will be the new volume of 200ml of 20degC water if the temperature is raised to 90degC
bull ∆V = 3σ ∆T Vo
bull = 3 x 69e-6degC x 70degC x 200ml
bull = 2898ml
bull Vnew = Vold + ∆V
bull Vnew = 200ml + 2898ml = 202898ml
Specific heat(CH2O) is the amount of heat required to raise the temperature of 1 kg of a material by one degree (Cdeg or K)
1) C(H2O) = 4184 J kg Cdeg
= 418 kJ kg Cdeg
2) C(sand) = 664 J kg CdegThis is why land heats up quickly during the day and
cools quickly at night and why water takes longer
How to calculate changes in thermal energy
Q = m x Cp x T
Q = quantity of thermal energy
m = mass of substance
T = change in temperature (Tf ndash Ti)
Cp = specific heat of substance(p)
Heat TransferHow much heat is required to warm
230 g of water from 12degC to 90degC
GIVENm = 230 gTi = 12degC
Tf = 90degC
Q = C(H2O)= 4184 JgmiddotoC
WORKQ = mmiddotTmiddotCp
m = 230 gT = 90degC - 12degC = 78degCQ = (230g)(78˚C)(4184 JgmiddotoC)Q = 75061 J
Calorimeters are used to measure the specific heat of a substance
Professional Kingrsquos Ridge
Laws of Thermodynamics
bull First Law Energy is always conservedo Energy added to a system may do two things
bull Increase the total thermal energy of the systembull Do work on the system
o Example Bicycle Pump puts air into tire(work) and heats the air(thermal)
bull Second Law Heat can travel from cold to hot ONLY if work is done on the systemo Example The compressor in a refrigerator
bull Third Law We will never reach Absolute Zero
Uses of Heatbull Heat Engines
o External Combustion Engines Fuel is burned outside of the engine
bull Steam Engine
Internal Combustiono Internal Combustion Engines Fuel is burned inside of the engine
bull Car engines
o 4 stroke engine Pistons are moving up and downbull Intake moving down intake valve open fuel mixture drawn
inbull Compression moving up both valves closedbull Power moving down both valves closed spark igniting fuelbull Exhaust moving up exhaust valve open waste exits
o Cooling system to keep the temperature of the engine within a specific range to prevent damage
o Electrical system Battery is used to start the engine then alternator is used to produce the electricity needed to run the engine and all other systems such as air conditioning
Heating Systemsbull Hot-Water Systemsmdashboilers and radiators -full of hot waterbull Steam Heat Systems-- ldquo -full of hot steambull Electric Heat Systemsmdashproducing heat(lightbulb)bull Forced Air Heating Systemsmdashmost homes todaym burning a fuel
and blowing the warmed air aroundbull Solar Heating using sunlight to heat water and homes
o Passivemdashallowing sunlight to enter home most efficiently and trapping it
o Activemdashcollecting solar energy then heating the home with the energy
bull Heat Pumps evaporators condensers amp coolanto Home Heatingmdashdrawing heat from the warm eartho Refrigeratormdashdrawing heat from the warm food and warm airo Air Conditionermdashdrawing heat from the warm room
The Law of Conservation of Energy
bull Man can neither create nor destroy Energy by ordinary meansoIt can only be converted from one form to another
oIf energy seems to disappear then scientists look for it ndash leading to many important discoveries
Law of Conservation of Energy
bull In 1905 Albert Einstein said that mass and energy can be converted into each other
bull He showed that if matter is destroyed energy is created and if energy is destroyed mass is created
bull E=MC2 bull M=mass C=speed of light
Power = measure of Energybull Work = Force x Distancebull Rate of doing Work orbull Amount of Workunit of timebull Power= WorkTime
bull Power = (Force x Distance)Time
bull Power Units = Watts bull 1Watt=1Joulesec or (1Nmsec)bull 1 Kilowatt = 1000 wattsbull 1 Horsepower = 746 watts
Thermal Energy (Heat) differs from
Temperature
Heat vs Temperaturebull Heat content is the TOTAL
KINETIC ENERGY of the particles in a sample
bull Temperature is the AVERAGE KINETIC ENERGY of the particles in a sample
Which has more Heat and which has the highest temperature
Insulatorsbull There are
thousands of air bubbles trapped in the styrofoam which slows down the heat flow through the layer
Insulation How do the Polar Bears stay warm in
the snow Their dense fine fir traps an air layer next to
their skin
Home Insulationbull The pink fiberglass
fibers trap air in the mat of insulation preventing heat from escaping in the winter or heat from entering during the summer Insulation
Highly Insulating Windows
bull Two or three panes between inside and outside air
bull Insulation is supplied by the Dead Air Space
Image source Southwall Technologies
Heat Transferbull Occurs three waysoConductionoConvectionoRadiation
bull The transfer of heat by direct contact between objects or particles
bull Motion of solid atoms or molecules carried from particle to particle
bull Heat transferred by the movement of molecules within liquid or gaseous substance
bull Warm rises cool sinks
bull A circular motion begins from warmer areas rising due to decreased density moving toward cooler areas which fall because of increased density
bull Wind and Major Weather patterns are caused and move largely because of these convection currents
bull Heat transferred through space
bull MATTER is not needed for radiation
bull EXAMPLE The sunrsquos rays carrying visible light and UV light causing sunburn
Radiationbull Transfer of heat through
electromagnetic radiation (light from stars or light bulbs)
bull Transferred in all directionsbull Matter is not requiredbull Dark or dull objects absorb
more than light or shiny objects do
Temperature
bull Temperature is a measure of the average KE of the particles in a sample of matter
Temperature Conversions
bull oC to oF oF = (95)oC + 32
bull oF to oC oC = 59(oF ndash 32)
bull oC to K K = oC + 273bull K to oC oC = K ndash 273
Going from Celsius to Fahrenheit
Convert 37 oC to oFoF = (95)oC + 32oF = (95)37oC + 32 = 666 + 32 = 986oF
Going from Fahrenheit to CelsiusConvert 68oF to oC
oC = 59(oF ndash 32)oC = 59(68 ndash 32)
= 59(36)
= 20 oC
Going from Kelvin to CelsiusConvert 310 K to oC
oC = K ndash 273oC = 310 ndash 273
= 37oC
Thermal Energybull Which beaker of water has more thermal
energyo B - same temperature but more mass
200 mL
80ordmC
A400 mL
80ordmC
B
Thermal energy relationships a As temperature increases so does
thermal energy (because the kinetic energy of the particles increased)
b Even if the temperature doesnrsquot change the thermal energy in a more massive substance is higher (because it is a total
measure of energy)
c Energy always travels from a high concentration(warm) to a lower concentration(cool) of heat
Land heats up and cools down faster than water The temperature of the water helps keep the
land temperature stable
Thermal Expansionbull Additional heat content causes matter to expandbull Loss of heat content causes matter to contractbull Faster particles take up more space
Sample Problem Thermal Expansion
bull What will be the new volume of 200ml of 20degC water if the temperature is raised to 90degC
bull ∆V = 3σ ∆T Vo
bull = 3 x 69e-6degC x 70degC x 200ml
bull = 2898ml
bull Vnew = Vold + ∆V
bull Vnew = 200ml + 2898ml = 202898ml
Specific heat(CH2O) is the amount of heat required to raise the temperature of 1 kg of a material by one degree (Cdeg or K)
1) C(H2O) = 4184 J kg Cdeg
= 418 kJ kg Cdeg
2) C(sand) = 664 J kg CdegThis is why land heats up quickly during the day and
cools quickly at night and why water takes longer
How to calculate changes in thermal energy
Q = m x Cp x T
Q = quantity of thermal energy
m = mass of substance
T = change in temperature (Tf ndash Ti)
Cp = specific heat of substance(p)
Heat TransferHow much heat is required to warm
230 g of water from 12degC to 90degC
GIVENm = 230 gTi = 12degC
Tf = 90degC
Q = C(H2O)= 4184 JgmiddotoC
WORKQ = mmiddotTmiddotCp
m = 230 gT = 90degC - 12degC = 78degCQ = (230g)(78˚C)(4184 JgmiddotoC)Q = 75061 J
Calorimeters are used to measure the specific heat of a substance
Professional Kingrsquos Ridge
Laws of Thermodynamics
bull First Law Energy is always conservedo Energy added to a system may do two things
bull Increase the total thermal energy of the systembull Do work on the system
o Example Bicycle Pump puts air into tire(work) and heats the air(thermal)
bull Second Law Heat can travel from cold to hot ONLY if work is done on the systemo Example The compressor in a refrigerator
bull Third Law We will never reach Absolute Zero
Uses of Heatbull Heat Engines
o External Combustion Engines Fuel is burned outside of the engine
bull Steam Engine
Internal Combustiono Internal Combustion Engines Fuel is burned inside of the engine
bull Car engines
o 4 stroke engine Pistons are moving up and downbull Intake moving down intake valve open fuel mixture drawn
inbull Compression moving up both valves closedbull Power moving down both valves closed spark igniting fuelbull Exhaust moving up exhaust valve open waste exits
o Cooling system to keep the temperature of the engine within a specific range to prevent damage
o Electrical system Battery is used to start the engine then alternator is used to produce the electricity needed to run the engine and all other systems such as air conditioning
Heating Systemsbull Hot-Water Systemsmdashboilers and radiators -full of hot waterbull Steam Heat Systems-- ldquo -full of hot steambull Electric Heat Systemsmdashproducing heat(lightbulb)bull Forced Air Heating Systemsmdashmost homes todaym burning a fuel
and blowing the warmed air aroundbull Solar Heating using sunlight to heat water and homes
o Passivemdashallowing sunlight to enter home most efficiently and trapping it
o Activemdashcollecting solar energy then heating the home with the energy
bull Heat Pumps evaporators condensers amp coolanto Home Heatingmdashdrawing heat from the warm eartho Refrigeratormdashdrawing heat from the warm food and warm airo Air Conditionermdashdrawing heat from the warm room
Law of Conservation of Energy
bull In 1905 Albert Einstein said that mass and energy can be converted into each other
bull He showed that if matter is destroyed energy is created and if energy is destroyed mass is created
bull E=MC2 bull M=mass C=speed of light
Power = measure of Energybull Work = Force x Distancebull Rate of doing Work orbull Amount of Workunit of timebull Power= WorkTime
bull Power = (Force x Distance)Time
bull Power Units = Watts bull 1Watt=1Joulesec or (1Nmsec)bull 1 Kilowatt = 1000 wattsbull 1 Horsepower = 746 watts
Thermal Energy (Heat) differs from
Temperature
Heat vs Temperaturebull Heat content is the TOTAL
KINETIC ENERGY of the particles in a sample
bull Temperature is the AVERAGE KINETIC ENERGY of the particles in a sample
Which has more Heat and which has the highest temperature
Insulatorsbull There are
thousands of air bubbles trapped in the styrofoam which slows down the heat flow through the layer
Insulation How do the Polar Bears stay warm in
the snow Their dense fine fir traps an air layer next to
their skin
Home Insulationbull The pink fiberglass
fibers trap air in the mat of insulation preventing heat from escaping in the winter or heat from entering during the summer Insulation
Highly Insulating Windows
bull Two or three panes between inside and outside air
bull Insulation is supplied by the Dead Air Space
Image source Southwall Technologies
Heat Transferbull Occurs three waysoConductionoConvectionoRadiation
bull The transfer of heat by direct contact between objects or particles
bull Motion of solid atoms or molecules carried from particle to particle
bull Heat transferred by the movement of molecules within liquid or gaseous substance
bull Warm rises cool sinks
bull A circular motion begins from warmer areas rising due to decreased density moving toward cooler areas which fall because of increased density
bull Wind and Major Weather patterns are caused and move largely because of these convection currents
bull Heat transferred through space
bull MATTER is not needed for radiation
bull EXAMPLE The sunrsquos rays carrying visible light and UV light causing sunburn
Radiationbull Transfer of heat through
electromagnetic radiation (light from stars or light bulbs)
bull Transferred in all directionsbull Matter is not requiredbull Dark or dull objects absorb
more than light or shiny objects do
Temperature
bull Temperature is a measure of the average KE of the particles in a sample of matter
Temperature Conversions
bull oC to oF oF = (95)oC + 32
bull oF to oC oC = 59(oF ndash 32)
bull oC to K K = oC + 273bull K to oC oC = K ndash 273
Going from Celsius to Fahrenheit
Convert 37 oC to oFoF = (95)oC + 32oF = (95)37oC + 32 = 666 + 32 = 986oF
Going from Fahrenheit to CelsiusConvert 68oF to oC
oC = 59(oF ndash 32)oC = 59(68 ndash 32)
= 59(36)
= 20 oC
Going from Kelvin to CelsiusConvert 310 K to oC
oC = K ndash 273oC = 310 ndash 273
= 37oC
Thermal Energybull Which beaker of water has more thermal
energyo B - same temperature but more mass
200 mL
80ordmC
A400 mL
80ordmC
B
Thermal energy relationships a As temperature increases so does
thermal energy (because the kinetic energy of the particles increased)
b Even if the temperature doesnrsquot change the thermal energy in a more massive substance is higher (because it is a total
measure of energy)
c Energy always travels from a high concentration(warm) to a lower concentration(cool) of heat
Land heats up and cools down faster than water The temperature of the water helps keep the
land temperature stable
Thermal Expansionbull Additional heat content causes matter to expandbull Loss of heat content causes matter to contractbull Faster particles take up more space
Sample Problem Thermal Expansion
bull What will be the new volume of 200ml of 20degC water if the temperature is raised to 90degC
bull ∆V = 3σ ∆T Vo
bull = 3 x 69e-6degC x 70degC x 200ml
bull = 2898ml
bull Vnew = Vold + ∆V
bull Vnew = 200ml + 2898ml = 202898ml
Specific heat(CH2O) is the amount of heat required to raise the temperature of 1 kg of a material by one degree (Cdeg or K)
1) C(H2O) = 4184 J kg Cdeg
= 418 kJ kg Cdeg
2) C(sand) = 664 J kg CdegThis is why land heats up quickly during the day and
cools quickly at night and why water takes longer
How to calculate changes in thermal energy
Q = m x Cp x T
Q = quantity of thermal energy
m = mass of substance
T = change in temperature (Tf ndash Ti)
Cp = specific heat of substance(p)
Heat TransferHow much heat is required to warm
230 g of water from 12degC to 90degC
GIVENm = 230 gTi = 12degC
Tf = 90degC
Q = C(H2O)= 4184 JgmiddotoC
WORKQ = mmiddotTmiddotCp
m = 230 gT = 90degC - 12degC = 78degCQ = (230g)(78˚C)(4184 JgmiddotoC)Q = 75061 J
Calorimeters are used to measure the specific heat of a substance
Professional Kingrsquos Ridge
Laws of Thermodynamics
bull First Law Energy is always conservedo Energy added to a system may do two things
bull Increase the total thermal energy of the systembull Do work on the system
o Example Bicycle Pump puts air into tire(work) and heats the air(thermal)
bull Second Law Heat can travel from cold to hot ONLY if work is done on the systemo Example The compressor in a refrigerator
bull Third Law We will never reach Absolute Zero
Uses of Heatbull Heat Engines
o External Combustion Engines Fuel is burned outside of the engine
bull Steam Engine
Internal Combustiono Internal Combustion Engines Fuel is burned inside of the engine
bull Car engines
o 4 stroke engine Pistons are moving up and downbull Intake moving down intake valve open fuel mixture drawn
inbull Compression moving up both valves closedbull Power moving down both valves closed spark igniting fuelbull Exhaust moving up exhaust valve open waste exits
o Cooling system to keep the temperature of the engine within a specific range to prevent damage
o Electrical system Battery is used to start the engine then alternator is used to produce the electricity needed to run the engine and all other systems such as air conditioning
Heating Systemsbull Hot-Water Systemsmdashboilers and radiators -full of hot waterbull Steam Heat Systems-- ldquo -full of hot steambull Electric Heat Systemsmdashproducing heat(lightbulb)bull Forced Air Heating Systemsmdashmost homes todaym burning a fuel
and blowing the warmed air aroundbull Solar Heating using sunlight to heat water and homes
o Passivemdashallowing sunlight to enter home most efficiently and trapping it
o Activemdashcollecting solar energy then heating the home with the energy
bull Heat Pumps evaporators condensers amp coolanto Home Heatingmdashdrawing heat from the warm eartho Refrigeratormdashdrawing heat from the warm food and warm airo Air Conditionermdashdrawing heat from the warm room
Power = measure of Energybull Work = Force x Distancebull Rate of doing Work orbull Amount of Workunit of timebull Power= WorkTime
bull Power = (Force x Distance)Time
bull Power Units = Watts bull 1Watt=1Joulesec or (1Nmsec)bull 1 Kilowatt = 1000 wattsbull 1 Horsepower = 746 watts
Thermal Energy (Heat) differs from
Temperature
Heat vs Temperaturebull Heat content is the TOTAL
KINETIC ENERGY of the particles in a sample
bull Temperature is the AVERAGE KINETIC ENERGY of the particles in a sample
Which has more Heat and which has the highest temperature
Insulatorsbull There are
thousands of air bubbles trapped in the styrofoam which slows down the heat flow through the layer
Insulation How do the Polar Bears stay warm in
the snow Their dense fine fir traps an air layer next to
their skin
Home Insulationbull The pink fiberglass
fibers trap air in the mat of insulation preventing heat from escaping in the winter or heat from entering during the summer Insulation
Highly Insulating Windows
bull Two or three panes between inside and outside air
bull Insulation is supplied by the Dead Air Space
Image source Southwall Technologies
Heat Transferbull Occurs three waysoConductionoConvectionoRadiation
bull The transfer of heat by direct contact between objects or particles
bull Motion of solid atoms or molecules carried from particle to particle
bull Heat transferred by the movement of molecules within liquid or gaseous substance
bull Warm rises cool sinks
bull A circular motion begins from warmer areas rising due to decreased density moving toward cooler areas which fall because of increased density
bull Wind and Major Weather patterns are caused and move largely because of these convection currents
bull Heat transferred through space
bull MATTER is not needed for radiation
bull EXAMPLE The sunrsquos rays carrying visible light and UV light causing sunburn
Radiationbull Transfer of heat through
electromagnetic radiation (light from stars or light bulbs)
bull Transferred in all directionsbull Matter is not requiredbull Dark or dull objects absorb
more than light or shiny objects do
Temperature
bull Temperature is a measure of the average KE of the particles in a sample of matter
Temperature Conversions
bull oC to oF oF = (95)oC + 32
bull oF to oC oC = 59(oF ndash 32)
bull oC to K K = oC + 273bull K to oC oC = K ndash 273
Going from Celsius to Fahrenheit
Convert 37 oC to oFoF = (95)oC + 32oF = (95)37oC + 32 = 666 + 32 = 986oF
Going from Fahrenheit to CelsiusConvert 68oF to oC
oC = 59(oF ndash 32)oC = 59(68 ndash 32)
= 59(36)
= 20 oC
Going from Kelvin to CelsiusConvert 310 K to oC
oC = K ndash 273oC = 310 ndash 273
= 37oC
Thermal Energybull Which beaker of water has more thermal
energyo B - same temperature but more mass
200 mL
80ordmC
A400 mL
80ordmC
B
Thermal energy relationships a As temperature increases so does
thermal energy (because the kinetic energy of the particles increased)
b Even if the temperature doesnrsquot change the thermal energy in a more massive substance is higher (because it is a total
measure of energy)
c Energy always travels from a high concentration(warm) to a lower concentration(cool) of heat
Land heats up and cools down faster than water The temperature of the water helps keep the
land temperature stable
Thermal Expansionbull Additional heat content causes matter to expandbull Loss of heat content causes matter to contractbull Faster particles take up more space
Sample Problem Thermal Expansion
bull What will be the new volume of 200ml of 20degC water if the temperature is raised to 90degC
bull ∆V = 3σ ∆T Vo
bull = 3 x 69e-6degC x 70degC x 200ml
bull = 2898ml
bull Vnew = Vold + ∆V
bull Vnew = 200ml + 2898ml = 202898ml
Specific heat(CH2O) is the amount of heat required to raise the temperature of 1 kg of a material by one degree (Cdeg or K)
1) C(H2O) = 4184 J kg Cdeg
= 418 kJ kg Cdeg
2) C(sand) = 664 J kg CdegThis is why land heats up quickly during the day and
cools quickly at night and why water takes longer
How to calculate changes in thermal energy
Q = m x Cp x T
Q = quantity of thermal energy
m = mass of substance
T = change in temperature (Tf ndash Ti)
Cp = specific heat of substance(p)
Heat TransferHow much heat is required to warm
230 g of water from 12degC to 90degC
GIVENm = 230 gTi = 12degC
Tf = 90degC
Q = C(H2O)= 4184 JgmiddotoC
WORKQ = mmiddotTmiddotCp
m = 230 gT = 90degC - 12degC = 78degCQ = (230g)(78˚C)(4184 JgmiddotoC)Q = 75061 J
Calorimeters are used to measure the specific heat of a substance
Professional Kingrsquos Ridge
Laws of Thermodynamics
bull First Law Energy is always conservedo Energy added to a system may do two things
bull Increase the total thermal energy of the systembull Do work on the system
o Example Bicycle Pump puts air into tire(work) and heats the air(thermal)
bull Second Law Heat can travel from cold to hot ONLY if work is done on the systemo Example The compressor in a refrigerator
bull Third Law We will never reach Absolute Zero
Uses of Heatbull Heat Engines
o External Combustion Engines Fuel is burned outside of the engine
bull Steam Engine
Internal Combustiono Internal Combustion Engines Fuel is burned inside of the engine
bull Car engines
o 4 stroke engine Pistons are moving up and downbull Intake moving down intake valve open fuel mixture drawn
inbull Compression moving up both valves closedbull Power moving down both valves closed spark igniting fuelbull Exhaust moving up exhaust valve open waste exits
o Cooling system to keep the temperature of the engine within a specific range to prevent damage
o Electrical system Battery is used to start the engine then alternator is used to produce the electricity needed to run the engine and all other systems such as air conditioning
Heating Systemsbull Hot-Water Systemsmdashboilers and radiators -full of hot waterbull Steam Heat Systems-- ldquo -full of hot steambull Electric Heat Systemsmdashproducing heat(lightbulb)bull Forced Air Heating Systemsmdashmost homes todaym burning a fuel
and blowing the warmed air aroundbull Solar Heating using sunlight to heat water and homes
o Passivemdashallowing sunlight to enter home most efficiently and trapping it
o Activemdashcollecting solar energy then heating the home with the energy
bull Heat Pumps evaporators condensers amp coolanto Home Heatingmdashdrawing heat from the warm eartho Refrigeratormdashdrawing heat from the warm food and warm airo Air Conditionermdashdrawing heat from the warm room
Thermal Energy (Heat) differs from
Temperature
Heat vs Temperaturebull Heat content is the TOTAL
KINETIC ENERGY of the particles in a sample
bull Temperature is the AVERAGE KINETIC ENERGY of the particles in a sample
Which has more Heat and which has the highest temperature
Insulatorsbull There are
thousands of air bubbles trapped in the styrofoam which slows down the heat flow through the layer
Insulation How do the Polar Bears stay warm in
the snow Their dense fine fir traps an air layer next to
their skin
Home Insulationbull The pink fiberglass
fibers trap air in the mat of insulation preventing heat from escaping in the winter or heat from entering during the summer Insulation
Highly Insulating Windows
bull Two or three panes between inside and outside air
bull Insulation is supplied by the Dead Air Space
Image source Southwall Technologies
Heat Transferbull Occurs three waysoConductionoConvectionoRadiation
bull The transfer of heat by direct contact between objects or particles
bull Motion of solid atoms or molecules carried from particle to particle
bull Heat transferred by the movement of molecules within liquid or gaseous substance
bull Warm rises cool sinks
bull A circular motion begins from warmer areas rising due to decreased density moving toward cooler areas which fall because of increased density
bull Wind and Major Weather patterns are caused and move largely because of these convection currents
bull Heat transferred through space
bull MATTER is not needed for radiation
bull EXAMPLE The sunrsquos rays carrying visible light and UV light causing sunburn
Radiationbull Transfer of heat through
electromagnetic radiation (light from stars or light bulbs)
bull Transferred in all directionsbull Matter is not requiredbull Dark or dull objects absorb
more than light or shiny objects do
Temperature
bull Temperature is a measure of the average KE of the particles in a sample of matter
Temperature Conversions
bull oC to oF oF = (95)oC + 32
bull oF to oC oC = 59(oF ndash 32)
bull oC to K K = oC + 273bull K to oC oC = K ndash 273
Going from Celsius to Fahrenheit
Convert 37 oC to oFoF = (95)oC + 32oF = (95)37oC + 32 = 666 + 32 = 986oF
Going from Fahrenheit to CelsiusConvert 68oF to oC
oC = 59(oF ndash 32)oC = 59(68 ndash 32)
= 59(36)
= 20 oC
Going from Kelvin to CelsiusConvert 310 K to oC
oC = K ndash 273oC = 310 ndash 273
= 37oC
Thermal Energybull Which beaker of water has more thermal
energyo B - same temperature but more mass
200 mL
80ordmC
A400 mL
80ordmC
B
Thermal energy relationships a As temperature increases so does
thermal energy (because the kinetic energy of the particles increased)
b Even if the temperature doesnrsquot change the thermal energy in a more massive substance is higher (because it is a total
measure of energy)
c Energy always travels from a high concentration(warm) to a lower concentration(cool) of heat
Land heats up and cools down faster than water The temperature of the water helps keep the
land temperature stable
Thermal Expansionbull Additional heat content causes matter to expandbull Loss of heat content causes matter to contractbull Faster particles take up more space
Sample Problem Thermal Expansion
bull What will be the new volume of 200ml of 20degC water if the temperature is raised to 90degC
bull ∆V = 3σ ∆T Vo
bull = 3 x 69e-6degC x 70degC x 200ml
bull = 2898ml
bull Vnew = Vold + ∆V
bull Vnew = 200ml + 2898ml = 202898ml
Specific heat(CH2O) is the amount of heat required to raise the temperature of 1 kg of a material by one degree (Cdeg or K)
1) C(H2O) = 4184 J kg Cdeg
= 418 kJ kg Cdeg
2) C(sand) = 664 J kg CdegThis is why land heats up quickly during the day and
cools quickly at night and why water takes longer
How to calculate changes in thermal energy
Q = m x Cp x T
Q = quantity of thermal energy
m = mass of substance
T = change in temperature (Tf ndash Ti)
Cp = specific heat of substance(p)
Heat TransferHow much heat is required to warm
230 g of water from 12degC to 90degC
GIVENm = 230 gTi = 12degC
Tf = 90degC
Q = C(H2O)= 4184 JgmiddotoC
WORKQ = mmiddotTmiddotCp
m = 230 gT = 90degC - 12degC = 78degCQ = (230g)(78˚C)(4184 JgmiddotoC)Q = 75061 J
Calorimeters are used to measure the specific heat of a substance
Professional Kingrsquos Ridge
Laws of Thermodynamics
bull First Law Energy is always conservedo Energy added to a system may do two things
bull Increase the total thermal energy of the systembull Do work on the system
o Example Bicycle Pump puts air into tire(work) and heats the air(thermal)
bull Second Law Heat can travel from cold to hot ONLY if work is done on the systemo Example The compressor in a refrigerator
bull Third Law We will never reach Absolute Zero
Uses of Heatbull Heat Engines
o External Combustion Engines Fuel is burned outside of the engine
bull Steam Engine
Internal Combustiono Internal Combustion Engines Fuel is burned inside of the engine
bull Car engines
o 4 stroke engine Pistons are moving up and downbull Intake moving down intake valve open fuel mixture drawn
inbull Compression moving up both valves closedbull Power moving down both valves closed spark igniting fuelbull Exhaust moving up exhaust valve open waste exits
o Cooling system to keep the temperature of the engine within a specific range to prevent damage
o Electrical system Battery is used to start the engine then alternator is used to produce the electricity needed to run the engine and all other systems such as air conditioning
Heating Systemsbull Hot-Water Systemsmdashboilers and radiators -full of hot waterbull Steam Heat Systems-- ldquo -full of hot steambull Electric Heat Systemsmdashproducing heat(lightbulb)bull Forced Air Heating Systemsmdashmost homes todaym burning a fuel
and blowing the warmed air aroundbull Solar Heating using sunlight to heat water and homes
o Passivemdashallowing sunlight to enter home most efficiently and trapping it
o Activemdashcollecting solar energy then heating the home with the energy
bull Heat Pumps evaporators condensers amp coolanto Home Heatingmdashdrawing heat from the warm eartho Refrigeratormdashdrawing heat from the warm food and warm airo Air Conditionermdashdrawing heat from the warm room
Heat vs Temperaturebull Heat content is the TOTAL
KINETIC ENERGY of the particles in a sample
bull Temperature is the AVERAGE KINETIC ENERGY of the particles in a sample
Which has more Heat and which has the highest temperature
Insulatorsbull There are
thousands of air bubbles trapped in the styrofoam which slows down the heat flow through the layer
Insulation How do the Polar Bears stay warm in
the snow Their dense fine fir traps an air layer next to
their skin
Home Insulationbull The pink fiberglass
fibers trap air in the mat of insulation preventing heat from escaping in the winter or heat from entering during the summer Insulation
Highly Insulating Windows
bull Two or three panes between inside and outside air
bull Insulation is supplied by the Dead Air Space
Image source Southwall Technologies
Heat Transferbull Occurs three waysoConductionoConvectionoRadiation
bull The transfer of heat by direct contact between objects or particles
bull Motion of solid atoms or molecules carried from particle to particle
bull Heat transferred by the movement of molecules within liquid or gaseous substance
bull Warm rises cool sinks
bull A circular motion begins from warmer areas rising due to decreased density moving toward cooler areas which fall because of increased density
bull Wind and Major Weather patterns are caused and move largely because of these convection currents
bull Heat transferred through space
bull MATTER is not needed for radiation
bull EXAMPLE The sunrsquos rays carrying visible light and UV light causing sunburn
Radiationbull Transfer of heat through
electromagnetic radiation (light from stars or light bulbs)
bull Transferred in all directionsbull Matter is not requiredbull Dark or dull objects absorb
more than light or shiny objects do
Temperature
bull Temperature is a measure of the average KE of the particles in a sample of matter
Temperature Conversions
bull oC to oF oF = (95)oC + 32
bull oF to oC oC = 59(oF ndash 32)
bull oC to K K = oC + 273bull K to oC oC = K ndash 273
Going from Celsius to Fahrenheit
Convert 37 oC to oFoF = (95)oC + 32oF = (95)37oC + 32 = 666 + 32 = 986oF
Going from Fahrenheit to CelsiusConvert 68oF to oC
oC = 59(oF ndash 32)oC = 59(68 ndash 32)
= 59(36)
= 20 oC
Going from Kelvin to CelsiusConvert 310 K to oC
oC = K ndash 273oC = 310 ndash 273
= 37oC
Thermal Energybull Which beaker of water has more thermal
energyo B - same temperature but more mass
200 mL
80ordmC
A400 mL
80ordmC
B
Thermal energy relationships a As temperature increases so does
thermal energy (because the kinetic energy of the particles increased)
b Even if the temperature doesnrsquot change the thermal energy in a more massive substance is higher (because it is a total
measure of energy)
c Energy always travels from a high concentration(warm) to a lower concentration(cool) of heat
Land heats up and cools down faster than water The temperature of the water helps keep the
land temperature stable
Thermal Expansionbull Additional heat content causes matter to expandbull Loss of heat content causes matter to contractbull Faster particles take up more space
Sample Problem Thermal Expansion
bull What will be the new volume of 200ml of 20degC water if the temperature is raised to 90degC
bull ∆V = 3σ ∆T Vo
bull = 3 x 69e-6degC x 70degC x 200ml
bull = 2898ml
bull Vnew = Vold + ∆V
bull Vnew = 200ml + 2898ml = 202898ml
Specific heat(CH2O) is the amount of heat required to raise the temperature of 1 kg of a material by one degree (Cdeg or K)
1) C(H2O) = 4184 J kg Cdeg
= 418 kJ kg Cdeg
2) C(sand) = 664 J kg CdegThis is why land heats up quickly during the day and
cools quickly at night and why water takes longer
How to calculate changes in thermal energy
Q = m x Cp x T
Q = quantity of thermal energy
m = mass of substance
T = change in temperature (Tf ndash Ti)
Cp = specific heat of substance(p)
Heat TransferHow much heat is required to warm
230 g of water from 12degC to 90degC
GIVENm = 230 gTi = 12degC
Tf = 90degC
Q = C(H2O)= 4184 JgmiddotoC
WORKQ = mmiddotTmiddotCp
m = 230 gT = 90degC - 12degC = 78degCQ = (230g)(78˚C)(4184 JgmiddotoC)Q = 75061 J
Calorimeters are used to measure the specific heat of a substance
Professional Kingrsquos Ridge
Laws of Thermodynamics
bull First Law Energy is always conservedo Energy added to a system may do two things
bull Increase the total thermal energy of the systembull Do work on the system
o Example Bicycle Pump puts air into tire(work) and heats the air(thermal)
bull Second Law Heat can travel from cold to hot ONLY if work is done on the systemo Example The compressor in a refrigerator
bull Third Law We will never reach Absolute Zero
Uses of Heatbull Heat Engines
o External Combustion Engines Fuel is burned outside of the engine
bull Steam Engine
Internal Combustiono Internal Combustion Engines Fuel is burned inside of the engine
bull Car engines
o 4 stroke engine Pistons are moving up and downbull Intake moving down intake valve open fuel mixture drawn
inbull Compression moving up both valves closedbull Power moving down both valves closed spark igniting fuelbull Exhaust moving up exhaust valve open waste exits
o Cooling system to keep the temperature of the engine within a specific range to prevent damage
o Electrical system Battery is used to start the engine then alternator is used to produce the electricity needed to run the engine and all other systems such as air conditioning
Heating Systemsbull Hot-Water Systemsmdashboilers and radiators -full of hot waterbull Steam Heat Systems-- ldquo -full of hot steambull Electric Heat Systemsmdashproducing heat(lightbulb)bull Forced Air Heating Systemsmdashmost homes todaym burning a fuel
and blowing the warmed air aroundbull Solar Heating using sunlight to heat water and homes
o Passivemdashallowing sunlight to enter home most efficiently and trapping it
o Activemdashcollecting solar energy then heating the home with the energy
bull Heat Pumps evaporators condensers amp coolanto Home Heatingmdashdrawing heat from the warm eartho Refrigeratormdashdrawing heat from the warm food and warm airo Air Conditionermdashdrawing heat from the warm room
Which has more Heat and which has the highest temperature
Insulatorsbull There are
thousands of air bubbles trapped in the styrofoam which slows down the heat flow through the layer
Insulation How do the Polar Bears stay warm in
the snow Their dense fine fir traps an air layer next to
their skin
Home Insulationbull The pink fiberglass
fibers trap air in the mat of insulation preventing heat from escaping in the winter or heat from entering during the summer Insulation
Highly Insulating Windows
bull Two or three panes between inside and outside air
bull Insulation is supplied by the Dead Air Space
Image source Southwall Technologies
Heat Transferbull Occurs three waysoConductionoConvectionoRadiation
bull The transfer of heat by direct contact between objects or particles
bull Motion of solid atoms or molecules carried from particle to particle
bull Heat transferred by the movement of molecules within liquid or gaseous substance
bull Warm rises cool sinks
bull A circular motion begins from warmer areas rising due to decreased density moving toward cooler areas which fall because of increased density
bull Wind and Major Weather patterns are caused and move largely because of these convection currents
bull Heat transferred through space
bull MATTER is not needed for radiation
bull EXAMPLE The sunrsquos rays carrying visible light and UV light causing sunburn
Radiationbull Transfer of heat through
electromagnetic radiation (light from stars or light bulbs)
bull Transferred in all directionsbull Matter is not requiredbull Dark or dull objects absorb
more than light or shiny objects do
Temperature
bull Temperature is a measure of the average KE of the particles in a sample of matter
Temperature Conversions
bull oC to oF oF = (95)oC + 32
bull oF to oC oC = 59(oF ndash 32)
bull oC to K K = oC + 273bull K to oC oC = K ndash 273
Going from Celsius to Fahrenheit
Convert 37 oC to oFoF = (95)oC + 32oF = (95)37oC + 32 = 666 + 32 = 986oF
Going from Fahrenheit to CelsiusConvert 68oF to oC
oC = 59(oF ndash 32)oC = 59(68 ndash 32)
= 59(36)
= 20 oC
Going from Kelvin to CelsiusConvert 310 K to oC
oC = K ndash 273oC = 310 ndash 273
= 37oC
Thermal Energybull Which beaker of water has more thermal
energyo B - same temperature but more mass
200 mL
80ordmC
A400 mL
80ordmC
B
Thermal energy relationships a As temperature increases so does
thermal energy (because the kinetic energy of the particles increased)
b Even if the temperature doesnrsquot change the thermal energy in a more massive substance is higher (because it is a total
measure of energy)
c Energy always travels from a high concentration(warm) to a lower concentration(cool) of heat
Land heats up and cools down faster than water The temperature of the water helps keep the
land temperature stable
Thermal Expansionbull Additional heat content causes matter to expandbull Loss of heat content causes matter to contractbull Faster particles take up more space
Sample Problem Thermal Expansion
bull What will be the new volume of 200ml of 20degC water if the temperature is raised to 90degC
bull ∆V = 3σ ∆T Vo
bull = 3 x 69e-6degC x 70degC x 200ml
bull = 2898ml
bull Vnew = Vold + ∆V
bull Vnew = 200ml + 2898ml = 202898ml
Specific heat(CH2O) is the amount of heat required to raise the temperature of 1 kg of a material by one degree (Cdeg or K)
1) C(H2O) = 4184 J kg Cdeg
= 418 kJ kg Cdeg
2) C(sand) = 664 J kg CdegThis is why land heats up quickly during the day and
cools quickly at night and why water takes longer
How to calculate changes in thermal energy
Q = m x Cp x T
Q = quantity of thermal energy
m = mass of substance
T = change in temperature (Tf ndash Ti)
Cp = specific heat of substance(p)
Heat TransferHow much heat is required to warm
230 g of water from 12degC to 90degC
GIVENm = 230 gTi = 12degC
Tf = 90degC
Q = C(H2O)= 4184 JgmiddotoC
WORKQ = mmiddotTmiddotCp
m = 230 gT = 90degC - 12degC = 78degCQ = (230g)(78˚C)(4184 JgmiddotoC)Q = 75061 J
Calorimeters are used to measure the specific heat of a substance
Professional Kingrsquos Ridge
Laws of Thermodynamics
bull First Law Energy is always conservedo Energy added to a system may do two things
bull Increase the total thermal energy of the systembull Do work on the system
o Example Bicycle Pump puts air into tire(work) and heats the air(thermal)
bull Second Law Heat can travel from cold to hot ONLY if work is done on the systemo Example The compressor in a refrigerator
bull Third Law We will never reach Absolute Zero
Uses of Heatbull Heat Engines
o External Combustion Engines Fuel is burned outside of the engine
bull Steam Engine
Internal Combustiono Internal Combustion Engines Fuel is burned inside of the engine
bull Car engines
o 4 stroke engine Pistons are moving up and downbull Intake moving down intake valve open fuel mixture drawn
inbull Compression moving up both valves closedbull Power moving down both valves closed spark igniting fuelbull Exhaust moving up exhaust valve open waste exits
o Cooling system to keep the temperature of the engine within a specific range to prevent damage
o Electrical system Battery is used to start the engine then alternator is used to produce the electricity needed to run the engine and all other systems such as air conditioning
Heating Systemsbull Hot-Water Systemsmdashboilers and radiators -full of hot waterbull Steam Heat Systems-- ldquo -full of hot steambull Electric Heat Systemsmdashproducing heat(lightbulb)bull Forced Air Heating Systemsmdashmost homes todaym burning a fuel
and blowing the warmed air aroundbull Solar Heating using sunlight to heat water and homes
o Passivemdashallowing sunlight to enter home most efficiently and trapping it
o Activemdashcollecting solar energy then heating the home with the energy
bull Heat Pumps evaporators condensers amp coolanto Home Heatingmdashdrawing heat from the warm eartho Refrigeratormdashdrawing heat from the warm food and warm airo Air Conditionermdashdrawing heat from the warm room
Insulatorsbull There are
thousands of air bubbles trapped in the styrofoam which slows down the heat flow through the layer
Insulation How do the Polar Bears stay warm in
the snow Their dense fine fir traps an air layer next to
their skin
Home Insulationbull The pink fiberglass
fibers trap air in the mat of insulation preventing heat from escaping in the winter or heat from entering during the summer Insulation
Highly Insulating Windows
bull Two or three panes between inside and outside air
bull Insulation is supplied by the Dead Air Space
Image source Southwall Technologies
Heat Transferbull Occurs three waysoConductionoConvectionoRadiation
bull The transfer of heat by direct contact between objects or particles
bull Motion of solid atoms or molecules carried from particle to particle
bull Heat transferred by the movement of molecules within liquid or gaseous substance
bull Warm rises cool sinks
bull A circular motion begins from warmer areas rising due to decreased density moving toward cooler areas which fall because of increased density
bull Wind and Major Weather patterns are caused and move largely because of these convection currents
bull Heat transferred through space
bull MATTER is not needed for radiation
bull EXAMPLE The sunrsquos rays carrying visible light and UV light causing sunburn
Radiationbull Transfer of heat through
electromagnetic radiation (light from stars or light bulbs)
bull Transferred in all directionsbull Matter is not requiredbull Dark or dull objects absorb
more than light or shiny objects do
Temperature
bull Temperature is a measure of the average KE of the particles in a sample of matter
Temperature Conversions
bull oC to oF oF = (95)oC + 32
bull oF to oC oC = 59(oF ndash 32)
bull oC to K K = oC + 273bull K to oC oC = K ndash 273
Going from Celsius to Fahrenheit
Convert 37 oC to oFoF = (95)oC + 32oF = (95)37oC + 32 = 666 + 32 = 986oF
Going from Fahrenheit to CelsiusConvert 68oF to oC
oC = 59(oF ndash 32)oC = 59(68 ndash 32)
= 59(36)
= 20 oC
Going from Kelvin to CelsiusConvert 310 K to oC
oC = K ndash 273oC = 310 ndash 273
= 37oC
Thermal Energybull Which beaker of water has more thermal
energyo B - same temperature but more mass
200 mL
80ordmC
A400 mL
80ordmC
B
Thermal energy relationships a As temperature increases so does
thermal energy (because the kinetic energy of the particles increased)
b Even if the temperature doesnrsquot change the thermal energy in a more massive substance is higher (because it is a total
measure of energy)
c Energy always travels from a high concentration(warm) to a lower concentration(cool) of heat
Land heats up and cools down faster than water The temperature of the water helps keep the
land temperature stable
Thermal Expansionbull Additional heat content causes matter to expandbull Loss of heat content causes matter to contractbull Faster particles take up more space
Sample Problem Thermal Expansion
bull What will be the new volume of 200ml of 20degC water if the temperature is raised to 90degC
bull ∆V = 3σ ∆T Vo
bull = 3 x 69e-6degC x 70degC x 200ml
bull = 2898ml
bull Vnew = Vold + ∆V
bull Vnew = 200ml + 2898ml = 202898ml
Specific heat(CH2O) is the amount of heat required to raise the temperature of 1 kg of a material by one degree (Cdeg or K)
1) C(H2O) = 4184 J kg Cdeg
= 418 kJ kg Cdeg
2) C(sand) = 664 J kg CdegThis is why land heats up quickly during the day and
cools quickly at night and why water takes longer
How to calculate changes in thermal energy
Q = m x Cp x T
Q = quantity of thermal energy
m = mass of substance
T = change in temperature (Tf ndash Ti)
Cp = specific heat of substance(p)
Heat TransferHow much heat is required to warm
230 g of water from 12degC to 90degC
GIVENm = 230 gTi = 12degC
Tf = 90degC
Q = C(H2O)= 4184 JgmiddotoC
WORKQ = mmiddotTmiddotCp
m = 230 gT = 90degC - 12degC = 78degCQ = (230g)(78˚C)(4184 JgmiddotoC)Q = 75061 J
Calorimeters are used to measure the specific heat of a substance
Professional Kingrsquos Ridge
Laws of Thermodynamics
bull First Law Energy is always conservedo Energy added to a system may do two things
bull Increase the total thermal energy of the systembull Do work on the system
o Example Bicycle Pump puts air into tire(work) and heats the air(thermal)
bull Second Law Heat can travel from cold to hot ONLY if work is done on the systemo Example The compressor in a refrigerator
bull Third Law We will never reach Absolute Zero
Uses of Heatbull Heat Engines
o External Combustion Engines Fuel is burned outside of the engine
bull Steam Engine
Internal Combustiono Internal Combustion Engines Fuel is burned inside of the engine
bull Car engines
o 4 stroke engine Pistons are moving up and downbull Intake moving down intake valve open fuel mixture drawn
inbull Compression moving up both valves closedbull Power moving down both valves closed spark igniting fuelbull Exhaust moving up exhaust valve open waste exits
o Cooling system to keep the temperature of the engine within a specific range to prevent damage
o Electrical system Battery is used to start the engine then alternator is used to produce the electricity needed to run the engine and all other systems such as air conditioning
Heating Systemsbull Hot-Water Systemsmdashboilers and radiators -full of hot waterbull Steam Heat Systems-- ldquo -full of hot steambull Electric Heat Systemsmdashproducing heat(lightbulb)bull Forced Air Heating Systemsmdashmost homes todaym burning a fuel
and blowing the warmed air aroundbull Solar Heating using sunlight to heat water and homes
o Passivemdashallowing sunlight to enter home most efficiently and trapping it
o Activemdashcollecting solar energy then heating the home with the energy
bull Heat Pumps evaporators condensers amp coolanto Home Heatingmdashdrawing heat from the warm eartho Refrigeratormdashdrawing heat from the warm food and warm airo Air Conditionermdashdrawing heat from the warm room
Insulation How do the Polar Bears stay warm in
the snow Their dense fine fir traps an air layer next to
their skin
Home Insulationbull The pink fiberglass
fibers trap air in the mat of insulation preventing heat from escaping in the winter or heat from entering during the summer Insulation
Highly Insulating Windows
bull Two or three panes between inside and outside air
bull Insulation is supplied by the Dead Air Space
Image source Southwall Technologies
Heat Transferbull Occurs three waysoConductionoConvectionoRadiation
bull The transfer of heat by direct contact between objects or particles
bull Motion of solid atoms or molecules carried from particle to particle
bull Heat transferred by the movement of molecules within liquid or gaseous substance
bull Warm rises cool sinks
bull A circular motion begins from warmer areas rising due to decreased density moving toward cooler areas which fall because of increased density
bull Wind and Major Weather patterns are caused and move largely because of these convection currents
bull Heat transferred through space
bull MATTER is not needed for radiation
bull EXAMPLE The sunrsquos rays carrying visible light and UV light causing sunburn
Radiationbull Transfer of heat through
electromagnetic radiation (light from stars or light bulbs)
bull Transferred in all directionsbull Matter is not requiredbull Dark or dull objects absorb
more than light or shiny objects do
Temperature
bull Temperature is a measure of the average KE of the particles in a sample of matter
Temperature Conversions
bull oC to oF oF = (95)oC + 32
bull oF to oC oC = 59(oF ndash 32)
bull oC to K K = oC + 273bull K to oC oC = K ndash 273
Going from Celsius to Fahrenheit
Convert 37 oC to oFoF = (95)oC + 32oF = (95)37oC + 32 = 666 + 32 = 986oF
Going from Fahrenheit to CelsiusConvert 68oF to oC
oC = 59(oF ndash 32)oC = 59(68 ndash 32)
= 59(36)
= 20 oC
Going from Kelvin to CelsiusConvert 310 K to oC
oC = K ndash 273oC = 310 ndash 273
= 37oC
Thermal Energybull Which beaker of water has more thermal
energyo B - same temperature but more mass
200 mL
80ordmC
A400 mL
80ordmC
B
Thermal energy relationships a As temperature increases so does
thermal energy (because the kinetic energy of the particles increased)
b Even if the temperature doesnrsquot change the thermal energy in a more massive substance is higher (because it is a total
measure of energy)
c Energy always travels from a high concentration(warm) to a lower concentration(cool) of heat
Land heats up and cools down faster than water The temperature of the water helps keep the
land temperature stable
Thermal Expansionbull Additional heat content causes matter to expandbull Loss of heat content causes matter to contractbull Faster particles take up more space
Sample Problem Thermal Expansion
bull What will be the new volume of 200ml of 20degC water if the temperature is raised to 90degC
bull ∆V = 3σ ∆T Vo
bull = 3 x 69e-6degC x 70degC x 200ml
bull = 2898ml
bull Vnew = Vold + ∆V
bull Vnew = 200ml + 2898ml = 202898ml
Specific heat(CH2O) is the amount of heat required to raise the temperature of 1 kg of a material by one degree (Cdeg or K)
1) C(H2O) = 4184 J kg Cdeg
= 418 kJ kg Cdeg
2) C(sand) = 664 J kg CdegThis is why land heats up quickly during the day and
cools quickly at night and why water takes longer
How to calculate changes in thermal energy
Q = m x Cp x T
Q = quantity of thermal energy
m = mass of substance
T = change in temperature (Tf ndash Ti)
Cp = specific heat of substance(p)
Heat TransferHow much heat is required to warm
230 g of water from 12degC to 90degC
GIVENm = 230 gTi = 12degC
Tf = 90degC
Q = C(H2O)= 4184 JgmiddotoC
WORKQ = mmiddotTmiddotCp
m = 230 gT = 90degC - 12degC = 78degCQ = (230g)(78˚C)(4184 JgmiddotoC)Q = 75061 J
Calorimeters are used to measure the specific heat of a substance
Professional Kingrsquos Ridge
Laws of Thermodynamics
bull First Law Energy is always conservedo Energy added to a system may do two things
bull Increase the total thermal energy of the systembull Do work on the system
o Example Bicycle Pump puts air into tire(work) and heats the air(thermal)
bull Second Law Heat can travel from cold to hot ONLY if work is done on the systemo Example The compressor in a refrigerator
bull Third Law We will never reach Absolute Zero
Uses of Heatbull Heat Engines
o External Combustion Engines Fuel is burned outside of the engine
bull Steam Engine
Internal Combustiono Internal Combustion Engines Fuel is burned inside of the engine
bull Car engines
o 4 stroke engine Pistons are moving up and downbull Intake moving down intake valve open fuel mixture drawn
inbull Compression moving up both valves closedbull Power moving down both valves closed spark igniting fuelbull Exhaust moving up exhaust valve open waste exits
o Cooling system to keep the temperature of the engine within a specific range to prevent damage
o Electrical system Battery is used to start the engine then alternator is used to produce the electricity needed to run the engine and all other systems such as air conditioning
Heating Systemsbull Hot-Water Systemsmdashboilers and radiators -full of hot waterbull Steam Heat Systems-- ldquo -full of hot steambull Electric Heat Systemsmdashproducing heat(lightbulb)bull Forced Air Heating Systemsmdashmost homes todaym burning a fuel
and blowing the warmed air aroundbull Solar Heating using sunlight to heat water and homes
o Passivemdashallowing sunlight to enter home most efficiently and trapping it
o Activemdashcollecting solar energy then heating the home with the energy
bull Heat Pumps evaporators condensers amp coolanto Home Heatingmdashdrawing heat from the warm eartho Refrigeratormdashdrawing heat from the warm food and warm airo Air Conditionermdashdrawing heat from the warm room
Home Insulationbull The pink fiberglass
fibers trap air in the mat of insulation preventing heat from escaping in the winter or heat from entering during the summer Insulation
Highly Insulating Windows
bull Two or three panes between inside and outside air
bull Insulation is supplied by the Dead Air Space
Image source Southwall Technologies
Heat Transferbull Occurs three waysoConductionoConvectionoRadiation
bull The transfer of heat by direct contact between objects or particles
bull Motion of solid atoms or molecules carried from particle to particle
bull Heat transferred by the movement of molecules within liquid or gaseous substance
bull Warm rises cool sinks
bull A circular motion begins from warmer areas rising due to decreased density moving toward cooler areas which fall because of increased density
bull Wind and Major Weather patterns are caused and move largely because of these convection currents
bull Heat transferred through space
bull MATTER is not needed for radiation
bull EXAMPLE The sunrsquos rays carrying visible light and UV light causing sunburn
Radiationbull Transfer of heat through
electromagnetic radiation (light from stars or light bulbs)
bull Transferred in all directionsbull Matter is not requiredbull Dark or dull objects absorb
more than light or shiny objects do
Temperature
bull Temperature is a measure of the average KE of the particles in a sample of matter
Temperature Conversions
bull oC to oF oF = (95)oC + 32
bull oF to oC oC = 59(oF ndash 32)
bull oC to K K = oC + 273bull K to oC oC = K ndash 273
Going from Celsius to Fahrenheit
Convert 37 oC to oFoF = (95)oC + 32oF = (95)37oC + 32 = 666 + 32 = 986oF
Going from Fahrenheit to CelsiusConvert 68oF to oC
oC = 59(oF ndash 32)oC = 59(68 ndash 32)
= 59(36)
= 20 oC
Going from Kelvin to CelsiusConvert 310 K to oC
oC = K ndash 273oC = 310 ndash 273
= 37oC
Thermal Energybull Which beaker of water has more thermal
energyo B - same temperature but more mass
200 mL
80ordmC
A400 mL
80ordmC
B
Thermal energy relationships a As temperature increases so does
thermal energy (because the kinetic energy of the particles increased)
b Even if the temperature doesnrsquot change the thermal energy in a more massive substance is higher (because it is a total
measure of energy)
c Energy always travels from a high concentration(warm) to a lower concentration(cool) of heat
Land heats up and cools down faster than water The temperature of the water helps keep the
land temperature stable
Thermal Expansionbull Additional heat content causes matter to expandbull Loss of heat content causes matter to contractbull Faster particles take up more space
Sample Problem Thermal Expansion
bull What will be the new volume of 200ml of 20degC water if the temperature is raised to 90degC
bull ∆V = 3σ ∆T Vo
bull = 3 x 69e-6degC x 70degC x 200ml
bull = 2898ml
bull Vnew = Vold + ∆V
bull Vnew = 200ml + 2898ml = 202898ml
Specific heat(CH2O) is the amount of heat required to raise the temperature of 1 kg of a material by one degree (Cdeg or K)
1) C(H2O) = 4184 J kg Cdeg
= 418 kJ kg Cdeg
2) C(sand) = 664 J kg CdegThis is why land heats up quickly during the day and
cools quickly at night and why water takes longer
How to calculate changes in thermal energy
Q = m x Cp x T
Q = quantity of thermal energy
m = mass of substance
T = change in temperature (Tf ndash Ti)
Cp = specific heat of substance(p)
Heat TransferHow much heat is required to warm
230 g of water from 12degC to 90degC
GIVENm = 230 gTi = 12degC
Tf = 90degC
Q = C(H2O)= 4184 JgmiddotoC
WORKQ = mmiddotTmiddotCp
m = 230 gT = 90degC - 12degC = 78degCQ = (230g)(78˚C)(4184 JgmiddotoC)Q = 75061 J
Calorimeters are used to measure the specific heat of a substance
Professional Kingrsquos Ridge
Laws of Thermodynamics
bull First Law Energy is always conservedo Energy added to a system may do two things
bull Increase the total thermal energy of the systembull Do work on the system
o Example Bicycle Pump puts air into tire(work) and heats the air(thermal)
bull Second Law Heat can travel from cold to hot ONLY if work is done on the systemo Example The compressor in a refrigerator
bull Third Law We will never reach Absolute Zero
Uses of Heatbull Heat Engines
o External Combustion Engines Fuel is burned outside of the engine
bull Steam Engine
Internal Combustiono Internal Combustion Engines Fuel is burned inside of the engine
bull Car engines
o 4 stroke engine Pistons are moving up and downbull Intake moving down intake valve open fuel mixture drawn
inbull Compression moving up both valves closedbull Power moving down both valves closed spark igniting fuelbull Exhaust moving up exhaust valve open waste exits
o Cooling system to keep the temperature of the engine within a specific range to prevent damage
o Electrical system Battery is used to start the engine then alternator is used to produce the electricity needed to run the engine and all other systems such as air conditioning
Heating Systemsbull Hot-Water Systemsmdashboilers and radiators -full of hot waterbull Steam Heat Systems-- ldquo -full of hot steambull Electric Heat Systemsmdashproducing heat(lightbulb)bull Forced Air Heating Systemsmdashmost homes todaym burning a fuel
and blowing the warmed air aroundbull Solar Heating using sunlight to heat water and homes
o Passivemdashallowing sunlight to enter home most efficiently and trapping it
o Activemdashcollecting solar energy then heating the home with the energy
bull Heat Pumps evaporators condensers amp coolanto Home Heatingmdashdrawing heat from the warm eartho Refrigeratormdashdrawing heat from the warm food and warm airo Air Conditionermdashdrawing heat from the warm room
Highly Insulating Windows
bull Two or three panes between inside and outside air
bull Insulation is supplied by the Dead Air Space
Image source Southwall Technologies
Heat Transferbull Occurs three waysoConductionoConvectionoRadiation
bull The transfer of heat by direct contact between objects or particles
bull Motion of solid atoms or molecules carried from particle to particle
bull Heat transferred by the movement of molecules within liquid or gaseous substance
bull Warm rises cool sinks
bull A circular motion begins from warmer areas rising due to decreased density moving toward cooler areas which fall because of increased density
bull Wind and Major Weather patterns are caused and move largely because of these convection currents
bull Heat transferred through space
bull MATTER is not needed for radiation
bull EXAMPLE The sunrsquos rays carrying visible light and UV light causing sunburn
Radiationbull Transfer of heat through
electromagnetic radiation (light from stars or light bulbs)
bull Transferred in all directionsbull Matter is not requiredbull Dark or dull objects absorb
more than light or shiny objects do
Temperature
bull Temperature is a measure of the average KE of the particles in a sample of matter
Temperature Conversions
bull oC to oF oF = (95)oC + 32
bull oF to oC oC = 59(oF ndash 32)
bull oC to K K = oC + 273bull K to oC oC = K ndash 273
Going from Celsius to Fahrenheit
Convert 37 oC to oFoF = (95)oC + 32oF = (95)37oC + 32 = 666 + 32 = 986oF
Going from Fahrenheit to CelsiusConvert 68oF to oC
oC = 59(oF ndash 32)oC = 59(68 ndash 32)
= 59(36)
= 20 oC
Going from Kelvin to CelsiusConvert 310 K to oC
oC = K ndash 273oC = 310 ndash 273
= 37oC
Thermal Energybull Which beaker of water has more thermal
energyo B - same temperature but more mass
200 mL
80ordmC
A400 mL
80ordmC
B
Thermal energy relationships a As temperature increases so does
thermal energy (because the kinetic energy of the particles increased)
b Even if the temperature doesnrsquot change the thermal energy in a more massive substance is higher (because it is a total
measure of energy)
c Energy always travels from a high concentration(warm) to a lower concentration(cool) of heat
Land heats up and cools down faster than water The temperature of the water helps keep the
land temperature stable
Thermal Expansionbull Additional heat content causes matter to expandbull Loss of heat content causes matter to contractbull Faster particles take up more space
Sample Problem Thermal Expansion
bull What will be the new volume of 200ml of 20degC water if the temperature is raised to 90degC
bull ∆V = 3σ ∆T Vo
bull = 3 x 69e-6degC x 70degC x 200ml
bull = 2898ml
bull Vnew = Vold + ∆V
bull Vnew = 200ml + 2898ml = 202898ml
Specific heat(CH2O) is the amount of heat required to raise the temperature of 1 kg of a material by one degree (Cdeg or K)
1) C(H2O) = 4184 J kg Cdeg
= 418 kJ kg Cdeg
2) C(sand) = 664 J kg CdegThis is why land heats up quickly during the day and
cools quickly at night and why water takes longer
How to calculate changes in thermal energy
Q = m x Cp x T
Q = quantity of thermal energy
m = mass of substance
T = change in temperature (Tf ndash Ti)
Cp = specific heat of substance(p)
Heat TransferHow much heat is required to warm
230 g of water from 12degC to 90degC
GIVENm = 230 gTi = 12degC
Tf = 90degC
Q = C(H2O)= 4184 JgmiddotoC
WORKQ = mmiddotTmiddotCp
m = 230 gT = 90degC - 12degC = 78degCQ = (230g)(78˚C)(4184 JgmiddotoC)Q = 75061 J
Calorimeters are used to measure the specific heat of a substance
Professional Kingrsquos Ridge
Laws of Thermodynamics
bull First Law Energy is always conservedo Energy added to a system may do two things
bull Increase the total thermal energy of the systembull Do work on the system
o Example Bicycle Pump puts air into tire(work) and heats the air(thermal)
bull Second Law Heat can travel from cold to hot ONLY if work is done on the systemo Example The compressor in a refrigerator
bull Third Law We will never reach Absolute Zero
Uses of Heatbull Heat Engines
o External Combustion Engines Fuel is burned outside of the engine
bull Steam Engine
Internal Combustiono Internal Combustion Engines Fuel is burned inside of the engine
bull Car engines
o 4 stroke engine Pistons are moving up and downbull Intake moving down intake valve open fuel mixture drawn
inbull Compression moving up both valves closedbull Power moving down both valves closed spark igniting fuelbull Exhaust moving up exhaust valve open waste exits
o Cooling system to keep the temperature of the engine within a specific range to prevent damage
o Electrical system Battery is used to start the engine then alternator is used to produce the electricity needed to run the engine and all other systems such as air conditioning
Heating Systemsbull Hot-Water Systemsmdashboilers and radiators -full of hot waterbull Steam Heat Systems-- ldquo -full of hot steambull Electric Heat Systemsmdashproducing heat(lightbulb)bull Forced Air Heating Systemsmdashmost homes todaym burning a fuel
and blowing the warmed air aroundbull Solar Heating using sunlight to heat water and homes
o Passivemdashallowing sunlight to enter home most efficiently and trapping it
o Activemdashcollecting solar energy then heating the home with the energy
bull Heat Pumps evaporators condensers amp coolanto Home Heatingmdashdrawing heat from the warm eartho Refrigeratormdashdrawing heat from the warm food and warm airo Air Conditionermdashdrawing heat from the warm room
Heat Transferbull Occurs three waysoConductionoConvectionoRadiation
bull The transfer of heat by direct contact between objects or particles
bull Motion of solid atoms or molecules carried from particle to particle
bull Heat transferred by the movement of molecules within liquid or gaseous substance
bull Warm rises cool sinks
bull A circular motion begins from warmer areas rising due to decreased density moving toward cooler areas which fall because of increased density
bull Wind and Major Weather patterns are caused and move largely because of these convection currents
bull Heat transferred through space
bull MATTER is not needed for radiation
bull EXAMPLE The sunrsquos rays carrying visible light and UV light causing sunburn
Radiationbull Transfer of heat through
electromagnetic radiation (light from stars or light bulbs)
bull Transferred in all directionsbull Matter is not requiredbull Dark or dull objects absorb
more than light or shiny objects do
Temperature
bull Temperature is a measure of the average KE of the particles in a sample of matter
Temperature Conversions
bull oC to oF oF = (95)oC + 32
bull oF to oC oC = 59(oF ndash 32)
bull oC to K K = oC + 273bull K to oC oC = K ndash 273
Going from Celsius to Fahrenheit
Convert 37 oC to oFoF = (95)oC + 32oF = (95)37oC + 32 = 666 + 32 = 986oF
Going from Fahrenheit to CelsiusConvert 68oF to oC
oC = 59(oF ndash 32)oC = 59(68 ndash 32)
= 59(36)
= 20 oC
Going from Kelvin to CelsiusConvert 310 K to oC
oC = K ndash 273oC = 310 ndash 273
= 37oC
Thermal Energybull Which beaker of water has more thermal
energyo B - same temperature but more mass
200 mL
80ordmC
A400 mL
80ordmC
B
Thermal energy relationships a As temperature increases so does
thermal energy (because the kinetic energy of the particles increased)
b Even if the temperature doesnrsquot change the thermal energy in a more massive substance is higher (because it is a total
measure of energy)
c Energy always travels from a high concentration(warm) to a lower concentration(cool) of heat
Land heats up and cools down faster than water The temperature of the water helps keep the
land temperature stable
Thermal Expansionbull Additional heat content causes matter to expandbull Loss of heat content causes matter to contractbull Faster particles take up more space
Sample Problem Thermal Expansion
bull What will be the new volume of 200ml of 20degC water if the temperature is raised to 90degC
bull ∆V = 3σ ∆T Vo
bull = 3 x 69e-6degC x 70degC x 200ml
bull = 2898ml
bull Vnew = Vold + ∆V
bull Vnew = 200ml + 2898ml = 202898ml
Specific heat(CH2O) is the amount of heat required to raise the temperature of 1 kg of a material by one degree (Cdeg or K)
1) C(H2O) = 4184 J kg Cdeg
= 418 kJ kg Cdeg
2) C(sand) = 664 J kg CdegThis is why land heats up quickly during the day and
cools quickly at night and why water takes longer
How to calculate changes in thermal energy
Q = m x Cp x T
Q = quantity of thermal energy
m = mass of substance
T = change in temperature (Tf ndash Ti)
Cp = specific heat of substance(p)
Heat TransferHow much heat is required to warm
230 g of water from 12degC to 90degC
GIVENm = 230 gTi = 12degC
Tf = 90degC
Q = C(H2O)= 4184 JgmiddotoC
WORKQ = mmiddotTmiddotCp
m = 230 gT = 90degC - 12degC = 78degCQ = (230g)(78˚C)(4184 JgmiddotoC)Q = 75061 J
Calorimeters are used to measure the specific heat of a substance
Professional Kingrsquos Ridge
Laws of Thermodynamics
bull First Law Energy is always conservedo Energy added to a system may do two things
bull Increase the total thermal energy of the systembull Do work on the system
o Example Bicycle Pump puts air into tire(work) and heats the air(thermal)
bull Second Law Heat can travel from cold to hot ONLY if work is done on the systemo Example The compressor in a refrigerator
bull Third Law We will never reach Absolute Zero
Uses of Heatbull Heat Engines
o External Combustion Engines Fuel is burned outside of the engine
bull Steam Engine
Internal Combustiono Internal Combustion Engines Fuel is burned inside of the engine
bull Car engines
o 4 stroke engine Pistons are moving up and downbull Intake moving down intake valve open fuel mixture drawn
inbull Compression moving up both valves closedbull Power moving down both valves closed spark igniting fuelbull Exhaust moving up exhaust valve open waste exits
o Cooling system to keep the temperature of the engine within a specific range to prevent damage
o Electrical system Battery is used to start the engine then alternator is used to produce the electricity needed to run the engine and all other systems such as air conditioning
Heating Systemsbull Hot-Water Systemsmdashboilers and radiators -full of hot waterbull Steam Heat Systems-- ldquo -full of hot steambull Electric Heat Systemsmdashproducing heat(lightbulb)bull Forced Air Heating Systemsmdashmost homes todaym burning a fuel
and blowing the warmed air aroundbull Solar Heating using sunlight to heat water and homes
o Passivemdashallowing sunlight to enter home most efficiently and trapping it
o Activemdashcollecting solar energy then heating the home with the energy
bull Heat Pumps evaporators condensers amp coolanto Home Heatingmdashdrawing heat from the warm eartho Refrigeratormdashdrawing heat from the warm food and warm airo Air Conditionermdashdrawing heat from the warm room
bull The transfer of heat by direct contact between objects or particles
bull Motion of solid atoms or molecules carried from particle to particle
bull Heat transferred by the movement of molecules within liquid or gaseous substance
bull Warm rises cool sinks
bull A circular motion begins from warmer areas rising due to decreased density moving toward cooler areas which fall because of increased density
bull Wind and Major Weather patterns are caused and move largely because of these convection currents
bull Heat transferred through space
bull MATTER is not needed for radiation
bull EXAMPLE The sunrsquos rays carrying visible light and UV light causing sunburn
Radiationbull Transfer of heat through
electromagnetic radiation (light from stars or light bulbs)
bull Transferred in all directionsbull Matter is not requiredbull Dark or dull objects absorb
more than light or shiny objects do
Temperature
bull Temperature is a measure of the average KE of the particles in a sample of matter
Temperature Conversions
bull oC to oF oF = (95)oC + 32
bull oF to oC oC = 59(oF ndash 32)
bull oC to K K = oC + 273bull K to oC oC = K ndash 273
Going from Celsius to Fahrenheit
Convert 37 oC to oFoF = (95)oC + 32oF = (95)37oC + 32 = 666 + 32 = 986oF
Going from Fahrenheit to CelsiusConvert 68oF to oC
oC = 59(oF ndash 32)oC = 59(68 ndash 32)
= 59(36)
= 20 oC
Going from Kelvin to CelsiusConvert 310 K to oC
oC = K ndash 273oC = 310 ndash 273
= 37oC
Thermal Energybull Which beaker of water has more thermal
energyo B - same temperature but more mass
200 mL
80ordmC
A400 mL
80ordmC
B
Thermal energy relationships a As temperature increases so does
thermal energy (because the kinetic energy of the particles increased)
b Even if the temperature doesnrsquot change the thermal energy in a more massive substance is higher (because it is a total
measure of energy)
c Energy always travels from a high concentration(warm) to a lower concentration(cool) of heat
Land heats up and cools down faster than water The temperature of the water helps keep the
land temperature stable
Thermal Expansionbull Additional heat content causes matter to expandbull Loss of heat content causes matter to contractbull Faster particles take up more space
Sample Problem Thermal Expansion
bull What will be the new volume of 200ml of 20degC water if the temperature is raised to 90degC
bull ∆V = 3σ ∆T Vo
bull = 3 x 69e-6degC x 70degC x 200ml
bull = 2898ml
bull Vnew = Vold + ∆V
bull Vnew = 200ml + 2898ml = 202898ml
Specific heat(CH2O) is the amount of heat required to raise the temperature of 1 kg of a material by one degree (Cdeg or K)
1) C(H2O) = 4184 J kg Cdeg
= 418 kJ kg Cdeg
2) C(sand) = 664 J kg CdegThis is why land heats up quickly during the day and
cools quickly at night and why water takes longer
How to calculate changes in thermal energy
Q = m x Cp x T
Q = quantity of thermal energy
m = mass of substance
T = change in temperature (Tf ndash Ti)
Cp = specific heat of substance(p)
Heat TransferHow much heat is required to warm
230 g of water from 12degC to 90degC
GIVENm = 230 gTi = 12degC
Tf = 90degC
Q = C(H2O)= 4184 JgmiddotoC
WORKQ = mmiddotTmiddotCp
m = 230 gT = 90degC - 12degC = 78degCQ = (230g)(78˚C)(4184 JgmiddotoC)Q = 75061 J
Calorimeters are used to measure the specific heat of a substance
Professional Kingrsquos Ridge
Laws of Thermodynamics
bull First Law Energy is always conservedo Energy added to a system may do two things
bull Increase the total thermal energy of the systembull Do work on the system
o Example Bicycle Pump puts air into tire(work) and heats the air(thermal)
bull Second Law Heat can travel from cold to hot ONLY if work is done on the systemo Example The compressor in a refrigerator
bull Third Law We will never reach Absolute Zero
Uses of Heatbull Heat Engines
o External Combustion Engines Fuel is burned outside of the engine
bull Steam Engine
Internal Combustiono Internal Combustion Engines Fuel is burned inside of the engine
bull Car engines
o 4 stroke engine Pistons are moving up and downbull Intake moving down intake valve open fuel mixture drawn
inbull Compression moving up both valves closedbull Power moving down both valves closed spark igniting fuelbull Exhaust moving up exhaust valve open waste exits
o Cooling system to keep the temperature of the engine within a specific range to prevent damage
o Electrical system Battery is used to start the engine then alternator is used to produce the electricity needed to run the engine and all other systems such as air conditioning
Heating Systemsbull Hot-Water Systemsmdashboilers and radiators -full of hot waterbull Steam Heat Systems-- ldquo -full of hot steambull Electric Heat Systemsmdashproducing heat(lightbulb)bull Forced Air Heating Systemsmdashmost homes todaym burning a fuel
and blowing the warmed air aroundbull Solar Heating using sunlight to heat water and homes
o Passivemdashallowing sunlight to enter home most efficiently and trapping it
o Activemdashcollecting solar energy then heating the home with the energy
bull Heat Pumps evaporators condensers amp coolanto Home Heatingmdashdrawing heat from the warm eartho Refrigeratormdashdrawing heat from the warm food and warm airo Air Conditionermdashdrawing heat from the warm room
bull Heat transferred by the movement of molecules within liquid or gaseous substance
bull Warm rises cool sinks
bull A circular motion begins from warmer areas rising due to decreased density moving toward cooler areas which fall because of increased density
bull Wind and Major Weather patterns are caused and move largely because of these convection currents
bull Heat transferred through space
bull MATTER is not needed for radiation
bull EXAMPLE The sunrsquos rays carrying visible light and UV light causing sunburn
Radiationbull Transfer of heat through
electromagnetic radiation (light from stars or light bulbs)
bull Transferred in all directionsbull Matter is not requiredbull Dark or dull objects absorb
more than light or shiny objects do
Temperature
bull Temperature is a measure of the average KE of the particles in a sample of matter
Temperature Conversions
bull oC to oF oF = (95)oC + 32
bull oF to oC oC = 59(oF ndash 32)
bull oC to K K = oC + 273bull K to oC oC = K ndash 273
Going from Celsius to Fahrenheit
Convert 37 oC to oFoF = (95)oC + 32oF = (95)37oC + 32 = 666 + 32 = 986oF
Going from Fahrenheit to CelsiusConvert 68oF to oC
oC = 59(oF ndash 32)oC = 59(68 ndash 32)
= 59(36)
= 20 oC
Going from Kelvin to CelsiusConvert 310 K to oC
oC = K ndash 273oC = 310 ndash 273
= 37oC
Thermal Energybull Which beaker of water has more thermal
energyo B - same temperature but more mass
200 mL
80ordmC
A400 mL
80ordmC
B
Thermal energy relationships a As temperature increases so does
thermal energy (because the kinetic energy of the particles increased)
b Even if the temperature doesnrsquot change the thermal energy in a more massive substance is higher (because it is a total
measure of energy)
c Energy always travels from a high concentration(warm) to a lower concentration(cool) of heat
Land heats up and cools down faster than water The temperature of the water helps keep the
land temperature stable
Thermal Expansionbull Additional heat content causes matter to expandbull Loss of heat content causes matter to contractbull Faster particles take up more space
Sample Problem Thermal Expansion
bull What will be the new volume of 200ml of 20degC water if the temperature is raised to 90degC
bull ∆V = 3σ ∆T Vo
bull = 3 x 69e-6degC x 70degC x 200ml
bull = 2898ml
bull Vnew = Vold + ∆V
bull Vnew = 200ml + 2898ml = 202898ml
Specific heat(CH2O) is the amount of heat required to raise the temperature of 1 kg of a material by one degree (Cdeg or K)
1) C(H2O) = 4184 J kg Cdeg
= 418 kJ kg Cdeg
2) C(sand) = 664 J kg CdegThis is why land heats up quickly during the day and
cools quickly at night and why water takes longer
How to calculate changes in thermal energy
Q = m x Cp x T
Q = quantity of thermal energy
m = mass of substance
T = change in temperature (Tf ndash Ti)
Cp = specific heat of substance(p)
Heat TransferHow much heat is required to warm
230 g of water from 12degC to 90degC
GIVENm = 230 gTi = 12degC
Tf = 90degC
Q = C(H2O)= 4184 JgmiddotoC
WORKQ = mmiddotTmiddotCp
m = 230 gT = 90degC - 12degC = 78degCQ = (230g)(78˚C)(4184 JgmiddotoC)Q = 75061 J
Calorimeters are used to measure the specific heat of a substance
Professional Kingrsquos Ridge
Laws of Thermodynamics
bull First Law Energy is always conservedo Energy added to a system may do two things
bull Increase the total thermal energy of the systembull Do work on the system
o Example Bicycle Pump puts air into tire(work) and heats the air(thermal)
bull Second Law Heat can travel from cold to hot ONLY if work is done on the systemo Example The compressor in a refrigerator
bull Third Law We will never reach Absolute Zero
Uses of Heatbull Heat Engines
o External Combustion Engines Fuel is burned outside of the engine
bull Steam Engine
Internal Combustiono Internal Combustion Engines Fuel is burned inside of the engine
bull Car engines
o 4 stroke engine Pistons are moving up and downbull Intake moving down intake valve open fuel mixture drawn
inbull Compression moving up both valves closedbull Power moving down both valves closed spark igniting fuelbull Exhaust moving up exhaust valve open waste exits
o Cooling system to keep the temperature of the engine within a specific range to prevent damage
o Electrical system Battery is used to start the engine then alternator is used to produce the electricity needed to run the engine and all other systems such as air conditioning
Heating Systemsbull Hot-Water Systemsmdashboilers and radiators -full of hot waterbull Steam Heat Systems-- ldquo -full of hot steambull Electric Heat Systemsmdashproducing heat(lightbulb)bull Forced Air Heating Systemsmdashmost homes todaym burning a fuel
and blowing the warmed air aroundbull Solar Heating using sunlight to heat water and homes
o Passivemdashallowing sunlight to enter home most efficiently and trapping it
o Activemdashcollecting solar energy then heating the home with the energy
bull Heat Pumps evaporators condensers amp coolanto Home Heatingmdashdrawing heat from the warm eartho Refrigeratormdashdrawing heat from the warm food and warm airo Air Conditionermdashdrawing heat from the warm room
bull Heat transferred through space
bull MATTER is not needed for radiation
bull EXAMPLE The sunrsquos rays carrying visible light and UV light causing sunburn
Radiationbull Transfer of heat through
electromagnetic radiation (light from stars or light bulbs)
bull Transferred in all directionsbull Matter is not requiredbull Dark or dull objects absorb
more than light or shiny objects do
Temperature
bull Temperature is a measure of the average KE of the particles in a sample of matter
Temperature Conversions
bull oC to oF oF = (95)oC + 32
bull oF to oC oC = 59(oF ndash 32)
bull oC to K K = oC + 273bull K to oC oC = K ndash 273
Going from Celsius to Fahrenheit
Convert 37 oC to oFoF = (95)oC + 32oF = (95)37oC + 32 = 666 + 32 = 986oF
Going from Fahrenheit to CelsiusConvert 68oF to oC
oC = 59(oF ndash 32)oC = 59(68 ndash 32)
= 59(36)
= 20 oC
Going from Kelvin to CelsiusConvert 310 K to oC
oC = K ndash 273oC = 310 ndash 273
= 37oC
Thermal Energybull Which beaker of water has more thermal
energyo B - same temperature but more mass
200 mL
80ordmC
A400 mL
80ordmC
B
Thermal energy relationships a As temperature increases so does
thermal energy (because the kinetic energy of the particles increased)
b Even if the temperature doesnrsquot change the thermal energy in a more massive substance is higher (because it is a total
measure of energy)
c Energy always travels from a high concentration(warm) to a lower concentration(cool) of heat
Land heats up and cools down faster than water The temperature of the water helps keep the
land temperature stable
Thermal Expansionbull Additional heat content causes matter to expandbull Loss of heat content causes matter to contractbull Faster particles take up more space
Sample Problem Thermal Expansion
bull What will be the new volume of 200ml of 20degC water if the temperature is raised to 90degC
bull ∆V = 3σ ∆T Vo
bull = 3 x 69e-6degC x 70degC x 200ml
bull = 2898ml
bull Vnew = Vold + ∆V
bull Vnew = 200ml + 2898ml = 202898ml
Specific heat(CH2O) is the amount of heat required to raise the temperature of 1 kg of a material by one degree (Cdeg or K)
1) C(H2O) = 4184 J kg Cdeg
= 418 kJ kg Cdeg
2) C(sand) = 664 J kg CdegThis is why land heats up quickly during the day and
cools quickly at night and why water takes longer
How to calculate changes in thermal energy
Q = m x Cp x T
Q = quantity of thermal energy
m = mass of substance
T = change in temperature (Tf ndash Ti)
Cp = specific heat of substance(p)
Heat TransferHow much heat is required to warm
230 g of water from 12degC to 90degC
GIVENm = 230 gTi = 12degC
Tf = 90degC
Q = C(H2O)= 4184 JgmiddotoC
WORKQ = mmiddotTmiddotCp
m = 230 gT = 90degC - 12degC = 78degCQ = (230g)(78˚C)(4184 JgmiddotoC)Q = 75061 J
Calorimeters are used to measure the specific heat of a substance
Professional Kingrsquos Ridge
Laws of Thermodynamics
bull First Law Energy is always conservedo Energy added to a system may do two things
bull Increase the total thermal energy of the systembull Do work on the system
o Example Bicycle Pump puts air into tire(work) and heats the air(thermal)
bull Second Law Heat can travel from cold to hot ONLY if work is done on the systemo Example The compressor in a refrigerator
bull Third Law We will never reach Absolute Zero
Uses of Heatbull Heat Engines
o External Combustion Engines Fuel is burned outside of the engine
bull Steam Engine
Internal Combustiono Internal Combustion Engines Fuel is burned inside of the engine
bull Car engines
o 4 stroke engine Pistons are moving up and downbull Intake moving down intake valve open fuel mixture drawn
inbull Compression moving up both valves closedbull Power moving down both valves closed spark igniting fuelbull Exhaust moving up exhaust valve open waste exits
o Cooling system to keep the temperature of the engine within a specific range to prevent damage
o Electrical system Battery is used to start the engine then alternator is used to produce the electricity needed to run the engine and all other systems such as air conditioning
Heating Systemsbull Hot-Water Systemsmdashboilers and radiators -full of hot waterbull Steam Heat Systems-- ldquo -full of hot steambull Electric Heat Systemsmdashproducing heat(lightbulb)bull Forced Air Heating Systemsmdashmost homes todaym burning a fuel
and blowing the warmed air aroundbull Solar Heating using sunlight to heat water and homes
o Passivemdashallowing sunlight to enter home most efficiently and trapping it
o Activemdashcollecting solar energy then heating the home with the energy
bull Heat Pumps evaporators condensers amp coolanto Home Heatingmdashdrawing heat from the warm eartho Refrigeratormdashdrawing heat from the warm food and warm airo Air Conditionermdashdrawing heat from the warm room
Radiationbull Transfer of heat through
electromagnetic radiation (light from stars or light bulbs)
bull Transferred in all directionsbull Matter is not requiredbull Dark or dull objects absorb
more than light or shiny objects do
Temperature
bull Temperature is a measure of the average KE of the particles in a sample of matter
Temperature Conversions
bull oC to oF oF = (95)oC + 32
bull oF to oC oC = 59(oF ndash 32)
bull oC to K K = oC + 273bull K to oC oC = K ndash 273
Going from Celsius to Fahrenheit
Convert 37 oC to oFoF = (95)oC + 32oF = (95)37oC + 32 = 666 + 32 = 986oF
Going from Fahrenheit to CelsiusConvert 68oF to oC
oC = 59(oF ndash 32)oC = 59(68 ndash 32)
= 59(36)
= 20 oC
Going from Kelvin to CelsiusConvert 310 K to oC
oC = K ndash 273oC = 310 ndash 273
= 37oC
Thermal Energybull Which beaker of water has more thermal
energyo B - same temperature but more mass
200 mL
80ordmC
A400 mL
80ordmC
B
Thermal energy relationships a As temperature increases so does
thermal energy (because the kinetic energy of the particles increased)
b Even if the temperature doesnrsquot change the thermal energy in a more massive substance is higher (because it is a total
measure of energy)
c Energy always travels from a high concentration(warm) to a lower concentration(cool) of heat
Land heats up and cools down faster than water The temperature of the water helps keep the
land temperature stable
Thermal Expansionbull Additional heat content causes matter to expandbull Loss of heat content causes matter to contractbull Faster particles take up more space
Sample Problem Thermal Expansion
bull What will be the new volume of 200ml of 20degC water if the temperature is raised to 90degC
bull ∆V = 3σ ∆T Vo
bull = 3 x 69e-6degC x 70degC x 200ml
bull = 2898ml
bull Vnew = Vold + ∆V
bull Vnew = 200ml + 2898ml = 202898ml
Specific heat(CH2O) is the amount of heat required to raise the temperature of 1 kg of a material by one degree (Cdeg or K)
1) C(H2O) = 4184 J kg Cdeg
= 418 kJ kg Cdeg
2) C(sand) = 664 J kg CdegThis is why land heats up quickly during the day and
cools quickly at night and why water takes longer
How to calculate changes in thermal energy
Q = m x Cp x T
Q = quantity of thermal energy
m = mass of substance
T = change in temperature (Tf ndash Ti)
Cp = specific heat of substance(p)
Heat TransferHow much heat is required to warm
230 g of water from 12degC to 90degC
GIVENm = 230 gTi = 12degC
Tf = 90degC
Q = C(H2O)= 4184 JgmiddotoC
WORKQ = mmiddotTmiddotCp
m = 230 gT = 90degC - 12degC = 78degCQ = (230g)(78˚C)(4184 JgmiddotoC)Q = 75061 J
Calorimeters are used to measure the specific heat of a substance
Professional Kingrsquos Ridge
Laws of Thermodynamics
bull First Law Energy is always conservedo Energy added to a system may do two things
bull Increase the total thermal energy of the systembull Do work on the system
o Example Bicycle Pump puts air into tire(work) and heats the air(thermal)
bull Second Law Heat can travel from cold to hot ONLY if work is done on the systemo Example The compressor in a refrigerator
bull Third Law We will never reach Absolute Zero
Uses of Heatbull Heat Engines
o External Combustion Engines Fuel is burned outside of the engine
bull Steam Engine
Internal Combustiono Internal Combustion Engines Fuel is burned inside of the engine
bull Car engines
o 4 stroke engine Pistons are moving up and downbull Intake moving down intake valve open fuel mixture drawn
inbull Compression moving up both valves closedbull Power moving down both valves closed spark igniting fuelbull Exhaust moving up exhaust valve open waste exits
o Cooling system to keep the temperature of the engine within a specific range to prevent damage
o Electrical system Battery is used to start the engine then alternator is used to produce the electricity needed to run the engine and all other systems such as air conditioning
Heating Systemsbull Hot-Water Systemsmdashboilers and radiators -full of hot waterbull Steam Heat Systems-- ldquo -full of hot steambull Electric Heat Systemsmdashproducing heat(lightbulb)bull Forced Air Heating Systemsmdashmost homes todaym burning a fuel
and blowing the warmed air aroundbull Solar Heating using sunlight to heat water and homes
o Passivemdashallowing sunlight to enter home most efficiently and trapping it
o Activemdashcollecting solar energy then heating the home with the energy
bull Heat Pumps evaporators condensers amp coolanto Home Heatingmdashdrawing heat from the warm eartho Refrigeratormdashdrawing heat from the warm food and warm airo Air Conditionermdashdrawing heat from the warm room
Temperature
bull Temperature is a measure of the average KE of the particles in a sample of matter
Temperature Conversions
bull oC to oF oF = (95)oC + 32
bull oF to oC oC = 59(oF ndash 32)
bull oC to K K = oC + 273bull K to oC oC = K ndash 273
Going from Celsius to Fahrenheit
Convert 37 oC to oFoF = (95)oC + 32oF = (95)37oC + 32 = 666 + 32 = 986oF
Going from Fahrenheit to CelsiusConvert 68oF to oC
oC = 59(oF ndash 32)oC = 59(68 ndash 32)
= 59(36)
= 20 oC
Going from Kelvin to CelsiusConvert 310 K to oC
oC = K ndash 273oC = 310 ndash 273
= 37oC
Thermal Energybull Which beaker of water has more thermal
energyo B - same temperature but more mass
200 mL
80ordmC
A400 mL
80ordmC
B
Thermal energy relationships a As temperature increases so does
thermal energy (because the kinetic energy of the particles increased)
b Even if the temperature doesnrsquot change the thermal energy in a more massive substance is higher (because it is a total
measure of energy)
c Energy always travels from a high concentration(warm) to a lower concentration(cool) of heat
Land heats up and cools down faster than water The temperature of the water helps keep the
land temperature stable
Thermal Expansionbull Additional heat content causes matter to expandbull Loss of heat content causes matter to contractbull Faster particles take up more space
Sample Problem Thermal Expansion
bull What will be the new volume of 200ml of 20degC water if the temperature is raised to 90degC
bull ∆V = 3σ ∆T Vo
bull = 3 x 69e-6degC x 70degC x 200ml
bull = 2898ml
bull Vnew = Vold + ∆V
bull Vnew = 200ml + 2898ml = 202898ml
Specific heat(CH2O) is the amount of heat required to raise the temperature of 1 kg of a material by one degree (Cdeg or K)
1) C(H2O) = 4184 J kg Cdeg
= 418 kJ kg Cdeg
2) C(sand) = 664 J kg CdegThis is why land heats up quickly during the day and
cools quickly at night and why water takes longer
How to calculate changes in thermal energy
Q = m x Cp x T
Q = quantity of thermal energy
m = mass of substance
T = change in temperature (Tf ndash Ti)
Cp = specific heat of substance(p)
Heat TransferHow much heat is required to warm
230 g of water from 12degC to 90degC
GIVENm = 230 gTi = 12degC
Tf = 90degC
Q = C(H2O)= 4184 JgmiddotoC
WORKQ = mmiddotTmiddotCp
m = 230 gT = 90degC - 12degC = 78degCQ = (230g)(78˚C)(4184 JgmiddotoC)Q = 75061 J
Calorimeters are used to measure the specific heat of a substance
Professional Kingrsquos Ridge
Laws of Thermodynamics
bull First Law Energy is always conservedo Energy added to a system may do two things
bull Increase the total thermal energy of the systembull Do work on the system
o Example Bicycle Pump puts air into tire(work) and heats the air(thermal)
bull Second Law Heat can travel from cold to hot ONLY if work is done on the systemo Example The compressor in a refrigerator
bull Third Law We will never reach Absolute Zero
Uses of Heatbull Heat Engines
o External Combustion Engines Fuel is burned outside of the engine
bull Steam Engine
Internal Combustiono Internal Combustion Engines Fuel is burned inside of the engine
bull Car engines
o 4 stroke engine Pistons are moving up and downbull Intake moving down intake valve open fuel mixture drawn
inbull Compression moving up both valves closedbull Power moving down both valves closed spark igniting fuelbull Exhaust moving up exhaust valve open waste exits
o Cooling system to keep the temperature of the engine within a specific range to prevent damage
o Electrical system Battery is used to start the engine then alternator is used to produce the electricity needed to run the engine and all other systems such as air conditioning
Heating Systemsbull Hot-Water Systemsmdashboilers and radiators -full of hot waterbull Steam Heat Systems-- ldquo -full of hot steambull Electric Heat Systemsmdashproducing heat(lightbulb)bull Forced Air Heating Systemsmdashmost homes todaym burning a fuel
and blowing the warmed air aroundbull Solar Heating using sunlight to heat water and homes
o Passivemdashallowing sunlight to enter home most efficiently and trapping it
o Activemdashcollecting solar energy then heating the home with the energy
bull Heat Pumps evaporators condensers amp coolanto Home Heatingmdashdrawing heat from the warm eartho Refrigeratormdashdrawing heat from the warm food and warm airo Air Conditionermdashdrawing heat from the warm room
Temperature Conversions
bull oC to oF oF = (95)oC + 32
bull oF to oC oC = 59(oF ndash 32)
bull oC to K K = oC + 273bull K to oC oC = K ndash 273
Going from Celsius to Fahrenheit
Convert 37 oC to oFoF = (95)oC + 32oF = (95)37oC + 32 = 666 + 32 = 986oF
Going from Fahrenheit to CelsiusConvert 68oF to oC
oC = 59(oF ndash 32)oC = 59(68 ndash 32)
= 59(36)
= 20 oC
Going from Kelvin to CelsiusConvert 310 K to oC
oC = K ndash 273oC = 310 ndash 273
= 37oC
Thermal Energybull Which beaker of water has more thermal
energyo B - same temperature but more mass
200 mL
80ordmC
A400 mL
80ordmC
B
Thermal energy relationships a As temperature increases so does
thermal energy (because the kinetic energy of the particles increased)
b Even if the temperature doesnrsquot change the thermal energy in a more massive substance is higher (because it is a total
measure of energy)
c Energy always travels from a high concentration(warm) to a lower concentration(cool) of heat
Land heats up and cools down faster than water The temperature of the water helps keep the
land temperature stable
Thermal Expansionbull Additional heat content causes matter to expandbull Loss of heat content causes matter to contractbull Faster particles take up more space
Sample Problem Thermal Expansion
bull What will be the new volume of 200ml of 20degC water if the temperature is raised to 90degC
bull ∆V = 3σ ∆T Vo
bull = 3 x 69e-6degC x 70degC x 200ml
bull = 2898ml
bull Vnew = Vold + ∆V
bull Vnew = 200ml + 2898ml = 202898ml
Specific heat(CH2O) is the amount of heat required to raise the temperature of 1 kg of a material by one degree (Cdeg or K)
1) C(H2O) = 4184 J kg Cdeg
= 418 kJ kg Cdeg
2) C(sand) = 664 J kg CdegThis is why land heats up quickly during the day and
cools quickly at night and why water takes longer
How to calculate changes in thermal energy
Q = m x Cp x T
Q = quantity of thermal energy
m = mass of substance
T = change in temperature (Tf ndash Ti)
Cp = specific heat of substance(p)
Heat TransferHow much heat is required to warm
230 g of water from 12degC to 90degC
GIVENm = 230 gTi = 12degC
Tf = 90degC
Q = C(H2O)= 4184 JgmiddotoC
WORKQ = mmiddotTmiddotCp
m = 230 gT = 90degC - 12degC = 78degCQ = (230g)(78˚C)(4184 JgmiddotoC)Q = 75061 J
Calorimeters are used to measure the specific heat of a substance
Professional Kingrsquos Ridge
Laws of Thermodynamics
bull First Law Energy is always conservedo Energy added to a system may do two things
bull Increase the total thermal energy of the systembull Do work on the system
o Example Bicycle Pump puts air into tire(work) and heats the air(thermal)
bull Second Law Heat can travel from cold to hot ONLY if work is done on the systemo Example The compressor in a refrigerator
bull Third Law We will never reach Absolute Zero
Uses of Heatbull Heat Engines
o External Combustion Engines Fuel is burned outside of the engine
bull Steam Engine
Internal Combustiono Internal Combustion Engines Fuel is burned inside of the engine
bull Car engines
o 4 stroke engine Pistons are moving up and downbull Intake moving down intake valve open fuel mixture drawn
inbull Compression moving up both valves closedbull Power moving down both valves closed spark igniting fuelbull Exhaust moving up exhaust valve open waste exits
o Cooling system to keep the temperature of the engine within a specific range to prevent damage
o Electrical system Battery is used to start the engine then alternator is used to produce the electricity needed to run the engine and all other systems such as air conditioning
Heating Systemsbull Hot-Water Systemsmdashboilers and radiators -full of hot waterbull Steam Heat Systems-- ldquo -full of hot steambull Electric Heat Systemsmdashproducing heat(lightbulb)bull Forced Air Heating Systemsmdashmost homes todaym burning a fuel
and blowing the warmed air aroundbull Solar Heating using sunlight to heat water and homes
o Passivemdashallowing sunlight to enter home most efficiently and trapping it
o Activemdashcollecting solar energy then heating the home with the energy
bull Heat Pumps evaporators condensers amp coolanto Home Heatingmdashdrawing heat from the warm eartho Refrigeratormdashdrawing heat from the warm food and warm airo Air Conditionermdashdrawing heat from the warm room
Going from Celsius to Fahrenheit
Convert 37 oC to oFoF = (95)oC + 32oF = (95)37oC + 32 = 666 + 32 = 986oF
Going from Fahrenheit to CelsiusConvert 68oF to oC
oC = 59(oF ndash 32)oC = 59(68 ndash 32)
= 59(36)
= 20 oC
Going from Kelvin to CelsiusConvert 310 K to oC
oC = K ndash 273oC = 310 ndash 273
= 37oC
Thermal Energybull Which beaker of water has more thermal
energyo B - same temperature but more mass
200 mL
80ordmC
A400 mL
80ordmC
B
Thermal energy relationships a As temperature increases so does
thermal energy (because the kinetic energy of the particles increased)
b Even if the temperature doesnrsquot change the thermal energy in a more massive substance is higher (because it is a total
measure of energy)
c Energy always travels from a high concentration(warm) to a lower concentration(cool) of heat
Land heats up and cools down faster than water The temperature of the water helps keep the
land temperature stable
Thermal Expansionbull Additional heat content causes matter to expandbull Loss of heat content causes matter to contractbull Faster particles take up more space
Sample Problem Thermal Expansion
bull What will be the new volume of 200ml of 20degC water if the temperature is raised to 90degC
bull ∆V = 3σ ∆T Vo
bull = 3 x 69e-6degC x 70degC x 200ml
bull = 2898ml
bull Vnew = Vold + ∆V
bull Vnew = 200ml + 2898ml = 202898ml
Specific heat(CH2O) is the amount of heat required to raise the temperature of 1 kg of a material by one degree (Cdeg or K)
1) C(H2O) = 4184 J kg Cdeg
= 418 kJ kg Cdeg
2) C(sand) = 664 J kg CdegThis is why land heats up quickly during the day and
cools quickly at night and why water takes longer
How to calculate changes in thermal energy
Q = m x Cp x T
Q = quantity of thermal energy
m = mass of substance
T = change in temperature (Tf ndash Ti)
Cp = specific heat of substance(p)
Heat TransferHow much heat is required to warm
230 g of water from 12degC to 90degC
GIVENm = 230 gTi = 12degC
Tf = 90degC
Q = C(H2O)= 4184 JgmiddotoC
WORKQ = mmiddotTmiddotCp
m = 230 gT = 90degC - 12degC = 78degCQ = (230g)(78˚C)(4184 JgmiddotoC)Q = 75061 J
Calorimeters are used to measure the specific heat of a substance
Professional Kingrsquos Ridge
Laws of Thermodynamics
bull First Law Energy is always conservedo Energy added to a system may do two things
bull Increase the total thermal energy of the systembull Do work on the system
o Example Bicycle Pump puts air into tire(work) and heats the air(thermal)
bull Second Law Heat can travel from cold to hot ONLY if work is done on the systemo Example The compressor in a refrigerator
bull Third Law We will never reach Absolute Zero
Uses of Heatbull Heat Engines
o External Combustion Engines Fuel is burned outside of the engine
bull Steam Engine
Internal Combustiono Internal Combustion Engines Fuel is burned inside of the engine
bull Car engines
o 4 stroke engine Pistons are moving up and downbull Intake moving down intake valve open fuel mixture drawn
inbull Compression moving up both valves closedbull Power moving down both valves closed spark igniting fuelbull Exhaust moving up exhaust valve open waste exits
o Cooling system to keep the temperature of the engine within a specific range to prevent damage
o Electrical system Battery is used to start the engine then alternator is used to produce the electricity needed to run the engine and all other systems such as air conditioning
Heating Systemsbull Hot-Water Systemsmdashboilers and radiators -full of hot waterbull Steam Heat Systems-- ldquo -full of hot steambull Electric Heat Systemsmdashproducing heat(lightbulb)bull Forced Air Heating Systemsmdashmost homes todaym burning a fuel
and blowing the warmed air aroundbull Solar Heating using sunlight to heat water and homes
o Passivemdashallowing sunlight to enter home most efficiently and trapping it
o Activemdashcollecting solar energy then heating the home with the energy
bull Heat Pumps evaporators condensers amp coolanto Home Heatingmdashdrawing heat from the warm eartho Refrigeratormdashdrawing heat from the warm food and warm airo Air Conditionermdashdrawing heat from the warm room
Going from Fahrenheit to CelsiusConvert 68oF to oC
oC = 59(oF ndash 32)oC = 59(68 ndash 32)
= 59(36)
= 20 oC
Going from Kelvin to CelsiusConvert 310 K to oC
oC = K ndash 273oC = 310 ndash 273
= 37oC
Thermal Energybull Which beaker of water has more thermal
energyo B - same temperature but more mass
200 mL
80ordmC
A400 mL
80ordmC
B
Thermal energy relationships a As temperature increases so does
thermal energy (because the kinetic energy of the particles increased)
b Even if the temperature doesnrsquot change the thermal energy in a more massive substance is higher (because it is a total
measure of energy)
c Energy always travels from a high concentration(warm) to a lower concentration(cool) of heat
Land heats up and cools down faster than water The temperature of the water helps keep the
land temperature stable
Thermal Expansionbull Additional heat content causes matter to expandbull Loss of heat content causes matter to contractbull Faster particles take up more space
Sample Problem Thermal Expansion
bull What will be the new volume of 200ml of 20degC water if the temperature is raised to 90degC
bull ∆V = 3σ ∆T Vo
bull = 3 x 69e-6degC x 70degC x 200ml
bull = 2898ml
bull Vnew = Vold + ∆V
bull Vnew = 200ml + 2898ml = 202898ml
Specific heat(CH2O) is the amount of heat required to raise the temperature of 1 kg of a material by one degree (Cdeg or K)
1) C(H2O) = 4184 J kg Cdeg
= 418 kJ kg Cdeg
2) C(sand) = 664 J kg CdegThis is why land heats up quickly during the day and
cools quickly at night and why water takes longer
How to calculate changes in thermal energy
Q = m x Cp x T
Q = quantity of thermal energy
m = mass of substance
T = change in temperature (Tf ndash Ti)
Cp = specific heat of substance(p)
Heat TransferHow much heat is required to warm
230 g of water from 12degC to 90degC
GIVENm = 230 gTi = 12degC
Tf = 90degC
Q = C(H2O)= 4184 JgmiddotoC
WORKQ = mmiddotTmiddotCp
m = 230 gT = 90degC - 12degC = 78degCQ = (230g)(78˚C)(4184 JgmiddotoC)Q = 75061 J
Calorimeters are used to measure the specific heat of a substance
Professional Kingrsquos Ridge
Laws of Thermodynamics
bull First Law Energy is always conservedo Energy added to a system may do two things
bull Increase the total thermal energy of the systembull Do work on the system
o Example Bicycle Pump puts air into tire(work) and heats the air(thermal)
bull Second Law Heat can travel from cold to hot ONLY if work is done on the systemo Example The compressor in a refrigerator
bull Third Law We will never reach Absolute Zero
Uses of Heatbull Heat Engines
o External Combustion Engines Fuel is burned outside of the engine
bull Steam Engine
Internal Combustiono Internal Combustion Engines Fuel is burned inside of the engine
bull Car engines
o 4 stroke engine Pistons are moving up and downbull Intake moving down intake valve open fuel mixture drawn
inbull Compression moving up both valves closedbull Power moving down both valves closed spark igniting fuelbull Exhaust moving up exhaust valve open waste exits
o Cooling system to keep the temperature of the engine within a specific range to prevent damage
o Electrical system Battery is used to start the engine then alternator is used to produce the electricity needed to run the engine and all other systems such as air conditioning
Heating Systemsbull Hot-Water Systemsmdashboilers and radiators -full of hot waterbull Steam Heat Systems-- ldquo -full of hot steambull Electric Heat Systemsmdashproducing heat(lightbulb)bull Forced Air Heating Systemsmdashmost homes todaym burning a fuel
and blowing the warmed air aroundbull Solar Heating using sunlight to heat water and homes
o Passivemdashallowing sunlight to enter home most efficiently and trapping it
o Activemdashcollecting solar energy then heating the home with the energy
bull Heat Pumps evaporators condensers amp coolanto Home Heatingmdashdrawing heat from the warm eartho Refrigeratormdashdrawing heat from the warm food and warm airo Air Conditionermdashdrawing heat from the warm room
Going from Kelvin to CelsiusConvert 310 K to oC
oC = K ndash 273oC = 310 ndash 273
= 37oC
Thermal Energybull Which beaker of water has more thermal
energyo B - same temperature but more mass
200 mL
80ordmC
A400 mL
80ordmC
B
Thermal energy relationships a As temperature increases so does
thermal energy (because the kinetic energy of the particles increased)
b Even if the temperature doesnrsquot change the thermal energy in a more massive substance is higher (because it is a total
measure of energy)
c Energy always travels from a high concentration(warm) to a lower concentration(cool) of heat
Land heats up and cools down faster than water The temperature of the water helps keep the
land temperature stable
Thermal Expansionbull Additional heat content causes matter to expandbull Loss of heat content causes matter to contractbull Faster particles take up more space
Sample Problem Thermal Expansion
bull What will be the new volume of 200ml of 20degC water if the temperature is raised to 90degC
bull ∆V = 3σ ∆T Vo
bull = 3 x 69e-6degC x 70degC x 200ml
bull = 2898ml
bull Vnew = Vold + ∆V
bull Vnew = 200ml + 2898ml = 202898ml
Specific heat(CH2O) is the amount of heat required to raise the temperature of 1 kg of a material by one degree (Cdeg or K)
1) C(H2O) = 4184 J kg Cdeg
= 418 kJ kg Cdeg
2) C(sand) = 664 J kg CdegThis is why land heats up quickly during the day and
cools quickly at night and why water takes longer
How to calculate changes in thermal energy
Q = m x Cp x T
Q = quantity of thermal energy
m = mass of substance
T = change in temperature (Tf ndash Ti)
Cp = specific heat of substance(p)
Heat TransferHow much heat is required to warm
230 g of water from 12degC to 90degC
GIVENm = 230 gTi = 12degC
Tf = 90degC
Q = C(H2O)= 4184 JgmiddotoC
WORKQ = mmiddotTmiddotCp
m = 230 gT = 90degC - 12degC = 78degCQ = (230g)(78˚C)(4184 JgmiddotoC)Q = 75061 J
Calorimeters are used to measure the specific heat of a substance
Professional Kingrsquos Ridge
Laws of Thermodynamics
bull First Law Energy is always conservedo Energy added to a system may do two things
bull Increase the total thermal energy of the systembull Do work on the system
o Example Bicycle Pump puts air into tire(work) and heats the air(thermal)
bull Second Law Heat can travel from cold to hot ONLY if work is done on the systemo Example The compressor in a refrigerator
bull Third Law We will never reach Absolute Zero
Uses of Heatbull Heat Engines
o External Combustion Engines Fuel is burned outside of the engine
bull Steam Engine
Internal Combustiono Internal Combustion Engines Fuel is burned inside of the engine
bull Car engines
o 4 stroke engine Pistons are moving up and downbull Intake moving down intake valve open fuel mixture drawn
inbull Compression moving up both valves closedbull Power moving down both valves closed spark igniting fuelbull Exhaust moving up exhaust valve open waste exits
o Cooling system to keep the temperature of the engine within a specific range to prevent damage
o Electrical system Battery is used to start the engine then alternator is used to produce the electricity needed to run the engine and all other systems such as air conditioning
Heating Systemsbull Hot-Water Systemsmdashboilers and radiators -full of hot waterbull Steam Heat Systems-- ldquo -full of hot steambull Electric Heat Systemsmdashproducing heat(lightbulb)bull Forced Air Heating Systemsmdashmost homes todaym burning a fuel
and blowing the warmed air aroundbull Solar Heating using sunlight to heat water and homes
o Passivemdashallowing sunlight to enter home most efficiently and trapping it
o Activemdashcollecting solar energy then heating the home with the energy
bull Heat Pumps evaporators condensers amp coolanto Home Heatingmdashdrawing heat from the warm eartho Refrigeratormdashdrawing heat from the warm food and warm airo Air Conditionermdashdrawing heat from the warm room
Thermal Energybull Which beaker of water has more thermal
energyo B - same temperature but more mass
200 mL
80ordmC
A400 mL
80ordmC
B
Thermal energy relationships a As temperature increases so does
thermal energy (because the kinetic energy of the particles increased)
b Even if the temperature doesnrsquot change the thermal energy in a more massive substance is higher (because it is a total
measure of energy)
c Energy always travels from a high concentration(warm) to a lower concentration(cool) of heat
Land heats up and cools down faster than water The temperature of the water helps keep the
land temperature stable
Thermal Expansionbull Additional heat content causes matter to expandbull Loss of heat content causes matter to contractbull Faster particles take up more space
Sample Problem Thermal Expansion
bull What will be the new volume of 200ml of 20degC water if the temperature is raised to 90degC
bull ∆V = 3σ ∆T Vo
bull = 3 x 69e-6degC x 70degC x 200ml
bull = 2898ml
bull Vnew = Vold + ∆V
bull Vnew = 200ml + 2898ml = 202898ml
Specific heat(CH2O) is the amount of heat required to raise the temperature of 1 kg of a material by one degree (Cdeg or K)
1) C(H2O) = 4184 J kg Cdeg
= 418 kJ kg Cdeg
2) C(sand) = 664 J kg CdegThis is why land heats up quickly during the day and
cools quickly at night and why water takes longer
How to calculate changes in thermal energy
Q = m x Cp x T
Q = quantity of thermal energy
m = mass of substance
T = change in temperature (Tf ndash Ti)
Cp = specific heat of substance(p)
Heat TransferHow much heat is required to warm
230 g of water from 12degC to 90degC
GIVENm = 230 gTi = 12degC
Tf = 90degC
Q = C(H2O)= 4184 JgmiddotoC
WORKQ = mmiddotTmiddotCp
m = 230 gT = 90degC - 12degC = 78degCQ = (230g)(78˚C)(4184 JgmiddotoC)Q = 75061 J
Calorimeters are used to measure the specific heat of a substance
Professional Kingrsquos Ridge
Laws of Thermodynamics
bull First Law Energy is always conservedo Energy added to a system may do two things
bull Increase the total thermal energy of the systembull Do work on the system
o Example Bicycle Pump puts air into tire(work) and heats the air(thermal)
bull Second Law Heat can travel from cold to hot ONLY if work is done on the systemo Example The compressor in a refrigerator
bull Third Law We will never reach Absolute Zero
Uses of Heatbull Heat Engines
o External Combustion Engines Fuel is burned outside of the engine
bull Steam Engine
Internal Combustiono Internal Combustion Engines Fuel is burned inside of the engine
bull Car engines
o 4 stroke engine Pistons are moving up and downbull Intake moving down intake valve open fuel mixture drawn
inbull Compression moving up both valves closedbull Power moving down both valves closed spark igniting fuelbull Exhaust moving up exhaust valve open waste exits
o Cooling system to keep the temperature of the engine within a specific range to prevent damage
o Electrical system Battery is used to start the engine then alternator is used to produce the electricity needed to run the engine and all other systems such as air conditioning
Heating Systemsbull Hot-Water Systemsmdashboilers and radiators -full of hot waterbull Steam Heat Systems-- ldquo -full of hot steambull Electric Heat Systemsmdashproducing heat(lightbulb)bull Forced Air Heating Systemsmdashmost homes todaym burning a fuel
and blowing the warmed air aroundbull Solar Heating using sunlight to heat water and homes
o Passivemdashallowing sunlight to enter home most efficiently and trapping it
o Activemdashcollecting solar energy then heating the home with the energy
bull Heat Pumps evaporators condensers amp coolanto Home Heatingmdashdrawing heat from the warm eartho Refrigeratormdashdrawing heat from the warm food and warm airo Air Conditionermdashdrawing heat from the warm room
Thermal energy relationships a As temperature increases so does
thermal energy (because the kinetic energy of the particles increased)
b Even if the temperature doesnrsquot change the thermal energy in a more massive substance is higher (because it is a total
measure of energy)
c Energy always travels from a high concentration(warm) to a lower concentration(cool) of heat
Land heats up and cools down faster than water The temperature of the water helps keep the
land temperature stable
Thermal Expansionbull Additional heat content causes matter to expandbull Loss of heat content causes matter to contractbull Faster particles take up more space
Sample Problem Thermal Expansion
bull What will be the new volume of 200ml of 20degC water if the temperature is raised to 90degC
bull ∆V = 3σ ∆T Vo
bull = 3 x 69e-6degC x 70degC x 200ml
bull = 2898ml
bull Vnew = Vold + ∆V
bull Vnew = 200ml + 2898ml = 202898ml
Specific heat(CH2O) is the amount of heat required to raise the temperature of 1 kg of a material by one degree (Cdeg or K)
1) C(H2O) = 4184 J kg Cdeg
= 418 kJ kg Cdeg
2) C(sand) = 664 J kg CdegThis is why land heats up quickly during the day and
cools quickly at night and why water takes longer
How to calculate changes in thermal energy
Q = m x Cp x T
Q = quantity of thermal energy
m = mass of substance
T = change in temperature (Tf ndash Ti)
Cp = specific heat of substance(p)
Heat TransferHow much heat is required to warm
230 g of water from 12degC to 90degC
GIVENm = 230 gTi = 12degC
Tf = 90degC
Q = C(H2O)= 4184 JgmiddotoC
WORKQ = mmiddotTmiddotCp
m = 230 gT = 90degC - 12degC = 78degCQ = (230g)(78˚C)(4184 JgmiddotoC)Q = 75061 J
Calorimeters are used to measure the specific heat of a substance
Professional Kingrsquos Ridge
Laws of Thermodynamics
bull First Law Energy is always conservedo Energy added to a system may do two things
bull Increase the total thermal energy of the systembull Do work on the system
o Example Bicycle Pump puts air into tire(work) and heats the air(thermal)
bull Second Law Heat can travel from cold to hot ONLY if work is done on the systemo Example The compressor in a refrigerator
bull Third Law We will never reach Absolute Zero
Uses of Heatbull Heat Engines
o External Combustion Engines Fuel is burned outside of the engine
bull Steam Engine
Internal Combustiono Internal Combustion Engines Fuel is burned inside of the engine
bull Car engines
o 4 stroke engine Pistons are moving up and downbull Intake moving down intake valve open fuel mixture drawn
inbull Compression moving up both valves closedbull Power moving down both valves closed spark igniting fuelbull Exhaust moving up exhaust valve open waste exits
o Cooling system to keep the temperature of the engine within a specific range to prevent damage
o Electrical system Battery is used to start the engine then alternator is used to produce the electricity needed to run the engine and all other systems such as air conditioning
Heating Systemsbull Hot-Water Systemsmdashboilers and radiators -full of hot waterbull Steam Heat Systems-- ldquo -full of hot steambull Electric Heat Systemsmdashproducing heat(lightbulb)bull Forced Air Heating Systemsmdashmost homes todaym burning a fuel
and blowing the warmed air aroundbull Solar Heating using sunlight to heat water and homes
o Passivemdashallowing sunlight to enter home most efficiently and trapping it
o Activemdashcollecting solar energy then heating the home with the energy
bull Heat Pumps evaporators condensers amp coolanto Home Heatingmdashdrawing heat from the warm eartho Refrigeratormdashdrawing heat from the warm food and warm airo Air Conditionermdashdrawing heat from the warm room
Land heats up and cools down faster than water The temperature of the water helps keep the
land temperature stable
Thermal Expansionbull Additional heat content causes matter to expandbull Loss of heat content causes matter to contractbull Faster particles take up more space
Sample Problem Thermal Expansion
bull What will be the new volume of 200ml of 20degC water if the temperature is raised to 90degC
bull ∆V = 3σ ∆T Vo
bull = 3 x 69e-6degC x 70degC x 200ml
bull = 2898ml
bull Vnew = Vold + ∆V
bull Vnew = 200ml + 2898ml = 202898ml
Specific heat(CH2O) is the amount of heat required to raise the temperature of 1 kg of a material by one degree (Cdeg or K)
1) C(H2O) = 4184 J kg Cdeg
= 418 kJ kg Cdeg
2) C(sand) = 664 J kg CdegThis is why land heats up quickly during the day and
cools quickly at night and why water takes longer
How to calculate changes in thermal energy
Q = m x Cp x T
Q = quantity of thermal energy
m = mass of substance
T = change in temperature (Tf ndash Ti)
Cp = specific heat of substance(p)
Heat TransferHow much heat is required to warm
230 g of water from 12degC to 90degC
GIVENm = 230 gTi = 12degC
Tf = 90degC
Q = C(H2O)= 4184 JgmiddotoC
WORKQ = mmiddotTmiddotCp
m = 230 gT = 90degC - 12degC = 78degCQ = (230g)(78˚C)(4184 JgmiddotoC)Q = 75061 J
Calorimeters are used to measure the specific heat of a substance
Professional Kingrsquos Ridge
Laws of Thermodynamics
bull First Law Energy is always conservedo Energy added to a system may do two things
bull Increase the total thermal energy of the systembull Do work on the system
o Example Bicycle Pump puts air into tire(work) and heats the air(thermal)
bull Second Law Heat can travel from cold to hot ONLY if work is done on the systemo Example The compressor in a refrigerator
bull Third Law We will never reach Absolute Zero
Uses of Heatbull Heat Engines
o External Combustion Engines Fuel is burned outside of the engine
bull Steam Engine
Internal Combustiono Internal Combustion Engines Fuel is burned inside of the engine
bull Car engines
o 4 stroke engine Pistons are moving up and downbull Intake moving down intake valve open fuel mixture drawn
inbull Compression moving up both valves closedbull Power moving down both valves closed spark igniting fuelbull Exhaust moving up exhaust valve open waste exits
o Cooling system to keep the temperature of the engine within a specific range to prevent damage
o Electrical system Battery is used to start the engine then alternator is used to produce the electricity needed to run the engine and all other systems such as air conditioning
Heating Systemsbull Hot-Water Systemsmdashboilers and radiators -full of hot waterbull Steam Heat Systems-- ldquo -full of hot steambull Electric Heat Systemsmdashproducing heat(lightbulb)bull Forced Air Heating Systemsmdashmost homes todaym burning a fuel
and blowing the warmed air aroundbull Solar Heating using sunlight to heat water and homes
o Passivemdashallowing sunlight to enter home most efficiently and trapping it
o Activemdashcollecting solar energy then heating the home with the energy
bull Heat Pumps evaporators condensers amp coolanto Home Heatingmdashdrawing heat from the warm eartho Refrigeratormdashdrawing heat from the warm food and warm airo Air Conditionermdashdrawing heat from the warm room
Thermal Expansionbull Additional heat content causes matter to expandbull Loss of heat content causes matter to contractbull Faster particles take up more space
Sample Problem Thermal Expansion
bull What will be the new volume of 200ml of 20degC water if the temperature is raised to 90degC
bull ∆V = 3σ ∆T Vo
bull = 3 x 69e-6degC x 70degC x 200ml
bull = 2898ml
bull Vnew = Vold + ∆V
bull Vnew = 200ml + 2898ml = 202898ml
Specific heat(CH2O) is the amount of heat required to raise the temperature of 1 kg of a material by one degree (Cdeg or K)
1) C(H2O) = 4184 J kg Cdeg
= 418 kJ kg Cdeg
2) C(sand) = 664 J kg CdegThis is why land heats up quickly during the day and
cools quickly at night and why water takes longer
How to calculate changes in thermal energy
Q = m x Cp x T
Q = quantity of thermal energy
m = mass of substance
T = change in temperature (Tf ndash Ti)
Cp = specific heat of substance(p)
Heat TransferHow much heat is required to warm
230 g of water from 12degC to 90degC
GIVENm = 230 gTi = 12degC
Tf = 90degC
Q = C(H2O)= 4184 JgmiddotoC
WORKQ = mmiddotTmiddotCp
m = 230 gT = 90degC - 12degC = 78degCQ = (230g)(78˚C)(4184 JgmiddotoC)Q = 75061 J
Calorimeters are used to measure the specific heat of a substance
Professional Kingrsquos Ridge
Laws of Thermodynamics
bull First Law Energy is always conservedo Energy added to a system may do two things
bull Increase the total thermal energy of the systembull Do work on the system
o Example Bicycle Pump puts air into tire(work) and heats the air(thermal)
bull Second Law Heat can travel from cold to hot ONLY if work is done on the systemo Example The compressor in a refrigerator
bull Third Law We will never reach Absolute Zero
Uses of Heatbull Heat Engines
o External Combustion Engines Fuel is burned outside of the engine
bull Steam Engine
Internal Combustiono Internal Combustion Engines Fuel is burned inside of the engine
bull Car engines
o 4 stroke engine Pistons are moving up and downbull Intake moving down intake valve open fuel mixture drawn
inbull Compression moving up both valves closedbull Power moving down both valves closed spark igniting fuelbull Exhaust moving up exhaust valve open waste exits
o Cooling system to keep the temperature of the engine within a specific range to prevent damage
o Electrical system Battery is used to start the engine then alternator is used to produce the electricity needed to run the engine and all other systems such as air conditioning
Heating Systemsbull Hot-Water Systemsmdashboilers and radiators -full of hot waterbull Steam Heat Systems-- ldquo -full of hot steambull Electric Heat Systemsmdashproducing heat(lightbulb)bull Forced Air Heating Systemsmdashmost homes todaym burning a fuel
and blowing the warmed air aroundbull Solar Heating using sunlight to heat water and homes
o Passivemdashallowing sunlight to enter home most efficiently and trapping it
o Activemdashcollecting solar energy then heating the home with the energy
bull Heat Pumps evaporators condensers amp coolanto Home Heatingmdashdrawing heat from the warm eartho Refrigeratormdashdrawing heat from the warm food and warm airo Air Conditionermdashdrawing heat from the warm room
Sample Problem Thermal Expansion
bull What will be the new volume of 200ml of 20degC water if the temperature is raised to 90degC
bull ∆V = 3σ ∆T Vo
bull = 3 x 69e-6degC x 70degC x 200ml
bull = 2898ml
bull Vnew = Vold + ∆V
bull Vnew = 200ml + 2898ml = 202898ml
Specific heat(CH2O) is the amount of heat required to raise the temperature of 1 kg of a material by one degree (Cdeg or K)
1) C(H2O) = 4184 J kg Cdeg
= 418 kJ kg Cdeg
2) C(sand) = 664 J kg CdegThis is why land heats up quickly during the day and
cools quickly at night and why water takes longer
How to calculate changes in thermal energy
Q = m x Cp x T
Q = quantity of thermal energy
m = mass of substance
T = change in temperature (Tf ndash Ti)
Cp = specific heat of substance(p)
Heat TransferHow much heat is required to warm
230 g of water from 12degC to 90degC
GIVENm = 230 gTi = 12degC
Tf = 90degC
Q = C(H2O)= 4184 JgmiddotoC
WORKQ = mmiddotTmiddotCp
m = 230 gT = 90degC - 12degC = 78degCQ = (230g)(78˚C)(4184 JgmiddotoC)Q = 75061 J
Calorimeters are used to measure the specific heat of a substance
Professional Kingrsquos Ridge
Laws of Thermodynamics
bull First Law Energy is always conservedo Energy added to a system may do two things
bull Increase the total thermal energy of the systembull Do work on the system
o Example Bicycle Pump puts air into tire(work) and heats the air(thermal)
bull Second Law Heat can travel from cold to hot ONLY if work is done on the systemo Example The compressor in a refrigerator
bull Third Law We will never reach Absolute Zero
Uses of Heatbull Heat Engines
o External Combustion Engines Fuel is burned outside of the engine
bull Steam Engine
Internal Combustiono Internal Combustion Engines Fuel is burned inside of the engine
bull Car engines
o 4 stroke engine Pistons are moving up and downbull Intake moving down intake valve open fuel mixture drawn
inbull Compression moving up both valves closedbull Power moving down both valves closed spark igniting fuelbull Exhaust moving up exhaust valve open waste exits
o Cooling system to keep the temperature of the engine within a specific range to prevent damage
o Electrical system Battery is used to start the engine then alternator is used to produce the electricity needed to run the engine and all other systems such as air conditioning
Heating Systemsbull Hot-Water Systemsmdashboilers and radiators -full of hot waterbull Steam Heat Systems-- ldquo -full of hot steambull Electric Heat Systemsmdashproducing heat(lightbulb)bull Forced Air Heating Systemsmdashmost homes todaym burning a fuel
and blowing the warmed air aroundbull Solar Heating using sunlight to heat water and homes
o Passivemdashallowing sunlight to enter home most efficiently and trapping it
o Activemdashcollecting solar energy then heating the home with the energy
bull Heat Pumps evaporators condensers amp coolanto Home Heatingmdashdrawing heat from the warm eartho Refrigeratormdashdrawing heat from the warm food and warm airo Air Conditionermdashdrawing heat from the warm room
Specific heat(CH2O) is the amount of heat required to raise the temperature of 1 kg of a material by one degree (Cdeg or K)
1) C(H2O) = 4184 J kg Cdeg
= 418 kJ kg Cdeg
2) C(sand) = 664 J kg CdegThis is why land heats up quickly during the day and
cools quickly at night and why water takes longer
How to calculate changes in thermal energy
Q = m x Cp x T
Q = quantity of thermal energy
m = mass of substance
T = change in temperature (Tf ndash Ti)
Cp = specific heat of substance(p)
Heat TransferHow much heat is required to warm
230 g of water from 12degC to 90degC
GIVENm = 230 gTi = 12degC
Tf = 90degC
Q = C(H2O)= 4184 JgmiddotoC
WORKQ = mmiddotTmiddotCp
m = 230 gT = 90degC - 12degC = 78degCQ = (230g)(78˚C)(4184 JgmiddotoC)Q = 75061 J
Calorimeters are used to measure the specific heat of a substance
Professional Kingrsquos Ridge
Laws of Thermodynamics
bull First Law Energy is always conservedo Energy added to a system may do two things
bull Increase the total thermal energy of the systembull Do work on the system
o Example Bicycle Pump puts air into tire(work) and heats the air(thermal)
bull Second Law Heat can travel from cold to hot ONLY if work is done on the systemo Example The compressor in a refrigerator
bull Third Law We will never reach Absolute Zero
Uses of Heatbull Heat Engines
o External Combustion Engines Fuel is burned outside of the engine
bull Steam Engine
Internal Combustiono Internal Combustion Engines Fuel is burned inside of the engine
bull Car engines
o 4 stroke engine Pistons are moving up and downbull Intake moving down intake valve open fuel mixture drawn
inbull Compression moving up both valves closedbull Power moving down both valves closed spark igniting fuelbull Exhaust moving up exhaust valve open waste exits
o Cooling system to keep the temperature of the engine within a specific range to prevent damage
o Electrical system Battery is used to start the engine then alternator is used to produce the electricity needed to run the engine and all other systems such as air conditioning
Heating Systemsbull Hot-Water Systemsmdashboilers and radiators -full of hot waterbull Steam Heat Systems-- ldquo -full of hot steambull Electric Heat Systemsmdashproducing heat(lightbulb)bull Forced Air Heating Systemsmdashmost homes todaym burning a fuel
and blowing the warmed air aroundbull Solar Heating using sunlight to heat water and homes
o Passivemdashallowing sunlight to enter home most efficiently and trapping it
o Activemdashcollecting solar energy then heating the home with the energy
bull Heat Pumps evaporators condensers amp coolanto Home Heatingmdashdrawing heat from the warm eartho Refrigeratormdashdrawing heat from the warm food and warm airo Air Conditionermdashdrawing heat from the warm room
How to calculate changes in thermal energy
Q = m x Cp x T
Q = quantity of thermal energy
m = mass of substance
T = change in temperature (Tf ndash Ti)
Cp = specific heat of substance(p)
Heat TransferHow much heat is required to warm
230 g of water from 12degC to 90degC
GIVENm = 230 gTi = 12degC
Tf = 90degC
Q = C(H2O)= 4184 JgmiddotoC
WORKQ = mmiddotTmiddotCp
m = 230 gT = 90degC - 12degC = 78degCQ = (230g)(78˚C)(4184 JgmiddotoC)Q = 75061 J
Calorimeters are used to measure the specific heat of a substance
Professional Kingrsquos Ridge
Laws of Thermodynamics
bull First Law Energy is always conservedo Energy added to a system may do two things
bull Increase the total thermal energy of the systembull Do work on the system
o Example Bicycle Pump puts air into tire(work) and heats the air(thermal)
bull Second Law Heat can travel from cold to hot ONLY if work is done on the systemo Example The compressor in a refrigerator
bull Third Law We will never reach Absolute Zero
Uses of Heatbull Heat Engines
o External Combustion Engines Fuel is burned outside of the engine
bull Steam Engine
Internal Combustiono Internal Combustion Engines Fuel is burned inside of the engine
bull Car engines
o 4 stroke engine Pistons are moving up and downbull Intake moving down intake valve open fuel mixture drawn
inbull Compression moving up both valves closedbull Power moving down both valves closed spark igniting fuelbull Exhaust moving up exhaust valve open waste exits
o Cooling system to keep the temperature of the engine within a specific range to prevent damage
o Electrical system Battery is used to start the engine then alternator is used to produce the electricity needed to run the engine and all other systems such as air conditioning
Heating Systemsbull Hot-Water Systemsmdashboilers and radiators -full of hot waterbull Steam Heat Systems-- ldquo -full of hot steambull Electric Heat Systemsmdashproducing heat(lightbulb)bull Forced Air Heating Systemsmdashmost homes todaym burning a fuel
and blowing the warmed air aroundbull Solar Heating using sunlight to heat water and homes
o Passivemdashallowing sunlight to enter home most efficiently and trapping it
o Activemdashcollecting solar energy then heating the home with the energy
bull Heat Pumps evaporators condensers amp coolanto Home Heatingmdashdrawing heat from the warm eartho Refrigeratormdashdrawing heat from the warm food and warm airo Air Conditionermdashdrawing heat from the warm room
Heat TransferHow much heat is required to warm
230 g of water from 12degC to 90degC
GIVENm = 230 gTi = 12degC
Tf = 90degC
Q = C(H2O)= 4184 JgmiddotoC
WORKQ = mmiddotTmiddotCp
m = 230 gT = 90degC - 12degC = 78degCQ = (230g)(78˚C)(4184 JgmiddotoC)Q = 75061 J
Calorimeters are used to measure the specific heat of a substance
Professional Kingrsquos Ridge
Laws of Thermodynamics
bull First Law Energy is always conservedo Energy added to a system may do two things
bull Increase the total thermal energy of the systembull Do work on the system
o Example Bicycle Pump puts air into tire(work) and heats the air(thermal)
bull Second Law Heat can travel from cold to hot ONLY if work is done on the systemo Example The compressor in a refrigerator
bull Third Law We will never reach Absolute Zero
Uses of Heatbull Heat Engines
o External Combustion Engines Fuel is burned outside of the engine
bull Steam Engine
Internal Combustiono Internal Combustion Engines Fuel is burned inside of the engine
bull Car engines
o 4 stroke engine Pistons are moving up and downbull Intake moving down intake valve open fuel mixture drawn
inbull Compression moving up both valves closedbull Power moving down both valves closed spark igniting fuelbull Exhaust moving up exhaust valve open waste exits
o Cooling system to keep the temperature of the engine within a specific range to prevent damage
o Electrical system Battery is used to start the engine then alternator is used to produce the electricity needed to run the engine and all other systems such as air conditioning
Heating Systemsbull Hot-Water Systemsmdashboilers and radiators -full of hot waterbull Steam Heat Systems-- ldquo -full of hot steambull Electric Heat Systemsmdashproducing heat(lightbulb)bull Forced Air Heating Systemsmdashmost homes todaym burning a fuel
and blowing the warmed air aroundbull Solar Heating using sunlight to heat water and homes
o Passivemdashallowing sunlight to enter home most efficiently and trapping it
o Activemdashcollecting solar energy then heating the home with the energy
bull Heat Pumps evaporators condensers amp coolanto Home Heatingmdashdrawing heat from the warm eartho Refrigeratormdashdrawing heat from the warm food and warm airo Air Conditionermdashdrawing heat from the warm room
Calorimeters are used to measure the specific heat of a substance
Professional Kingrsquos Ridge
Laws of Thermodynamics
bull First Law Energy is always conservedo Energy added to a system may do two things
bull Increase the total thermal energy of the systembull Do work on the system
o Example Bicycle Pump puts air into tire(work) and heats the air(thermal)
bull Second Law Heat can travel from cold to hot ONLY if work is done on the systemo Example The compressor in a refrigerator
bull Third Law We will never reach Absolute Zero
Uses of Heatbull Heat Engines
o External Combustion Engines Fuel is burned outside of the engine
bull Steam Engine
Internal Combustiono Internal Combustion Engines Fuel is burned inside of the engine
bull Car engines
o 4 stroke engine Pistons are moving up and downbull Intake moving down intake valve open fuel mixture drawn
inbull Compression moving up both valves closedbull Power moving down both valves closed spark igniting fuelbull Exhaust moving up exhaust valve open waste exits
o Cooling system to keep the temperature of the engine within a specific range to prevent damage
o Electrical system Battery is used to start the engine then alternator is used to produce the electricity needed to run the engine and all other systems such as air conditioning
Heating Systemsbull Hot-Water Systemsmdashboilers and radiators -full of hot waterbull Steam Heat Systems-- ldquo -full of hot steambull Electric Heat Systemsmdashproducing heat(lightbulb)bull Forced Air Heating Systemsmdashmost homes todaym burning a fuel
and blowing the warmed air aroundbull Solar Heating using sunlight to heat water and homes
o Passivemdashallowing sunlight to enter home most efficiently and trapping it
o Activemdashcollecting solar energy then heating the home with the energy
bull Heat Pumps evaporators condensers amp coolanto Home Heatingmdashdrawing heat from the warm eartho Refrigeratormdashdrawing heat from the warm food and warm airo Air Conditionermdashdrawing heat from the warm room
Laws of Thermodynamics
bull First Law Energy is always conservedo Energy added to a system may do two things
bull Increase the total thermal energy of the systembull Do work on the system
o Example Bicycle Pump puts air into tire(work) and heats the air(thermal)
bull Second Law Heat can travel from cold to hot ONLY if work is done on the systemo Example The compressor in a refrigerator
bull Third Law We will never reach Absolute Zero
Uses of Heatbull Heat Engines
o External Combustion Engines Fuel is burned outside of the engine
bull Steam Engine
Internal Combustiono Internal Combustion Engines Fuel is burned inside of the engine
bull Car engines
o 4 stroke engine Pistons are moving up and downbull Intake moving down intake valve open fuel mixture drawn
inbull Compression moving up both valves closedbull Power moving down both valves closed spark igniting fuelbull Exhaust moving up exhaust valve open waste exits
o Cooling system to keep the temperature of the engine within a specific range to prevent damage
o Electrical system Battery is used to start the engine then alternator is used to produce the electricity needed to run the engine and all other systems such as air conditioning
Heating Systemsbull Hot-Water Systemsmdashboilers and radiators -full of hot waterbull Steam Heat Systems-- ldquo -full of hot steambull Electric Heat Systemsmdashproducing heat(lightbulb)bull Forced Air Heating Systemsmdashmost homes todaym burning a fuel
and blowing the warmed air aroundbull Solar Heating using sunlight to heat water and homes
o Passivemdashallowing sunlight to enter home most efficiently and trapping it
o Activemdashcollecting solar energy then heating the home with the energy
bull Heat Pumps evaporators condensers amp coolanto Home Heatingmdashdrawing heat from the warm eartho Refrigeratormdashdrawing heat from the warm food and warm airo Air Conditionermdashdrawing heat from the warm room
Uses of Heatbull Heat Engines
o External Combustion Engines Fuel is burned outside of the engine
bull Steam Engine
Internal Combustiono Internal Combustion Engines Fuel is burned inside of the engine
bull Car engines
o 4 stroke engine Pistons are moving up and downbull Intake moving down intake valve open fuel mixture drawn
inbull Compression moving up both valves closedbull Power moving down both valves closed spark igniting fuelbull Exhaust moving up exhaust valve open waste exits
o Cooling system to keep the temperature of the engine within a specific range to prevent damage
o Electrical system Battery is used to start the engine then alternator is used to produce the electricity needed to run the engine and all other systems such as air conditioning
Heating Systemsbull Hot-Water Systemsmdashboilers and radiators -full of hot waterbull Steam Heat Systems-- ldquo -full of hot steambull Electric Heat Systemsmdashproducing heat(lightbulb)bull Forced Air Heating Systemsmdashmost homes todaym burning a fuel
and blowing the warmed air aroundbull Solar Heating using sunlight to heat water and homes
o Passivemdashallowing sunlight to enter home most efficiently and trapping it
o Activemdashcollecting solar energy then heating the home with the energy
bull Heat Pumps evaporators condensers amp coolanto Home Heatingmdashdrawing heat from the warm eartho Refrigeratormdashdrawing heat from the warm food and warm airo Air Conditionermdashdrawing heat from the warm room
Internal Combustiono Internal Combustion Engines Fuel is burned inside of the engine
bull Car engines
o 4 stroke engine Pistons are moving up and downbull Intake moving down intake valve open fuel mixture drawn
inbull Compression moving up both valves closedbull Power moving down both valves closed spark igniting fuelbull Exhaust moving up exhaust valve open waste exits
o Cooling system to keep the temperature of the engine within a specific range to prevent damage
o Electrical system Battery is used to start the engine then alternator is used to produce the electricity needed to run the engine and all other systems such as air conditioning
Heating Systemsbull Hot-Water Systemsmdashboilers and radiators -full of hot waterbull Steam Heat Systems-- ldquo -full of hot steambull Electric Heat Systemsmdashproducing heat(lightbulb)bull Forced Air Heating Systemsmdashmost homes todaym burning a fuel
and blowing the warmed air aroundbull Solar Heating using sunlight to heat water and homes
o Passivemdashallowing sunlight to enter home most efficiently and trapping it
o Activemdashcollecting solar energy then heating the home with the energy
bull Heat Pumps evaporators condensers amp coolanto Home Heatingmdashdrawing heat from the warm eartho Refrigeratormdashdrawing heat from the warm food and warm airo Air Conditionermdashdrawing heat from the warm room
Heating Systemsbull Hot-Water Systemsmdashboilers and radiators -full of hot waterbull Steam Heat Systems-- ldquo -full of hot steambull Electric Heat Systemsmdashproducing heat(lightbulb)bull Forced Air Heating Systemsmdashmost homes todaym burning a fuel
and blowing the warmed air aroundbull Solar Heating using sunlight to heat water and homes
o Passivemdashallowing sunlight to enter home most efficiently and trapping it
o Activemdashcollecting solar energy then heating the home with the energy
bull Heat Pumps evaporators condensers amp coolanto Home Heatingmdashdrawing heat from the warm eartho Refrigeratormdashdrawing heat from the warm food and warm airo Air Conditionermdashdrawing heat from the warm room
