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Energy Transfers Project.
Read this slide first…
Anywhere you see red writing will require a response.
All tasks will be highlighted in a yellow text box
Check your understanding
Put an X in the boxes to show how much you understand on the following topics
Topic
Types of energy
Energy stores and transfers
Energy efficiency
Power
What is energy ?
Energy can be defined as: -
‘ the ability to do work’ or ‘ the potential to cause change’
There are lots of different stores of energy that you are going to look at along with how they transfer from one energy store to another energy store.
Read the information
• Energy is a quantity, just like mass or distance
• Mass is measured in kg, distance in m, so what do we measure energy in?
• This guy helped discover laws of thermodynamics and the unit was named after him!
Energy is a quantityEnergy is measured in Joules, J.
Read the information
Describe what this shows?
Energy is measured in kilojoules!
(kilo means 1000, so 1 kilojoule is 1000 joules)
This is because food is a store of chemical energy
Stores of Energy
Energy can be stored in different ways.
Your money could be stored in a savings account or in your pocket, or it could even be placed in a shop’s till if you use it to buy something. Energy can also be found in different stores.
There are eight types of energy store:
1. A hot drink holds energy in a thermal store2. A moving car or moving particles holds energy in a kinetic store3. A stretched elastic band holds energy in an elastic store4. A ball placed on a high shelf holds energy in a gravitational store5. Batteries, petrol and food all hold energy in a chemical store6. A thunderstorm holds energy in an electrical store7. A magnet can hold energy in a magnetic store8. A radioactive atom, nuclear bomb or the core of the Sun holds energy in a nuclear store.
Read the information
https://www.youtube.com/watch?v=Z57kGB-mI54
Watch the video and try to spot the different types of energy stores and energy transfers.
The Principle of Conservation of energy:
Energy is transferred from one store to another, but it cannot be created or destroyed.
How many different types of energy store did you spot?
Answer here
All moving things have kinetic energy, even very large things like
planets, and very small ones like atoms. The amount of kinetic energy
an object has depends upon:
•the mass of the object
•the speed of the object
Kinetic energy Read the information
Internal energy
A hot cup of tea has more internal energy than a cold cup of tea
All objects have internal energy. This includes:
energy caused by the movement of particles in the object,
sometimes called thermal energy
energy due to the bonds between particles, sometimes called
chemical energy
Read the information
Some objects can change shape reversibly. Rubber balls,
springs and elastic bands are like this. When a rubber ball is
stretched or squashed, it can regain its shape again. Elastic potential energy is stored in stretched or squashed materials
Elastic potential energy
Elastic potential energy will be stored in this catapult when its
bands are stretched
Read the information
When an object is moved higher, it gains gravitational potential
energy. The amount of gravitational potential energy it gains depends
upon:
•the mass of the object
•the extra height it gains
•the gravitational field strength
Gravitational potential energy
These rocks store gravitational potential energy because of their height
above the ground
Gravitational potential energy Read the information
Some objects carry electrical charges and create electric
fields. These charged objects can exert forces on each
other. You get an electric current when charged particles move through a wire
Electrical energy Read the information
Magnetic energy
Some objects can be magnetised and create magnetic fields.
They can exert forces on other magnetised objects, or on magnetic materials
The magnetic field created by this bar magnet is shown using iron
filings
Read the information
Task Drag and drop the boxes so that they match up.
There should be a picture, name of the energy store and a description of the energy store
TASK
THER
MA
L
KIN
ETIC
ELA
STIC
GR
AV
ITA
TIO
NA
L
CH
EMIC
AL
ELEC
TRIC
AL
MA
GN
ETIC
NU
CLE
AR
CALCULATOR
DRY-CELL BATTERY × × × × × × ×HOT AIR-BALLOON
WATERFALL
CATAPULT
CHILD ON A SWING × × × × × ×EXPLOSION
SUN
Use copy and paste function to show which energy is used in each activity/process by inserting a tick or a cross. Two have been done for you
TASK – Complete the task.
1. An object at rest on top of a shelf is likely to have:
No energyGravitational potential energyHydroelectric power
2. Batteries are stores of:
Chemical energyElectrical energyLight energy
3 Energy is usefully transferred from a personal audio player as:
Kinetic energyThermal energySound energy
4 Which is likely to contain the most thermal energy?
A red hot horseshoeA spark from a fireworkAn ice cube
5 Which is likely to have the highest temperature?
A red hot horseshoeA spark from a fireworkAn ice cube
6. Thermal energy is transferred by conduction from:
The hot end to the cold endThe cold end to the hot endThe Sun to the Earth
7. What type of energy is stored in a wind up toy?
Elastic potentialGravitational potential energyHeat
Highlight the correct answer
Design your own theme park ride and label it with the different types of energy stores that are involved with making your ride the best ride there is. You can draw it on paper, photograph it and then attach to this PowerPoint. Or you can you upload a photo of your work direct into the Assignment dropbox in Teams.
Insert photo here
Design a Theme Park Ride
Energy transfer efficiency
Research why a bungee jumper never go as high as when they first started?
Energy Transfers in The Real World
When the rope is slack, some of the gravitational potential energy of the jumper is transferred into kinetic energy as the jumper falls. Some is also wasted as heat energy
Once the slack in the rope has been used up, the rope slows the bungee jumper’s fall. Most of the gravitational potential energy and kinetic energy of the jumper is transferred into elastic strain energy and even more heat energy
After reaching the bottom the rope pulls the jumper back up. As the jumper rises, most of the elastic strain energy of the rope is transferred back to gravitational potential energy and kinetic energy of the jumper. Some energy is also wasted as heat energy in the rope
Read the information
The law of conservation of energy
• Energy can be transferred in more than one form at a time.
• The INPUT energy will always equal the total OUTPUT energy.
• Any wasted energy will always go to the surroundings
“Energy cannot be created or destroyed. It can
only be changed from one form to another.”
Read the information
Conservation of Energy Energy cannot be created or destroyed. It can be stored and can be transferred from one type to another. Only part of the energy will be transferred usefully (to the type you want); the rest is ‘wasted’.
Energy in = energy out
Energy is measured in joules (J). If 100J goes into an appliance, then 100J will come out. But not all of the 100J coming out will be the type of energy you want.
Read the information
Electrical energy
100J
Heat energy20J
Kinetic energy22J
(Wasted vibration of the
drill)
Kinetic energy58J
(Useful spinning of the
drill bit)
Energy Transfer Values
Read the information
Answer here
Add the correct number of joules of sound.
Answer here
Answer here
Add the correct number of joules.
Appliance Input energy
(J)
Useful
energy (J)
Waste
Energy (J)
Tungsten filament light bulb 100 20
Energy efficient light bulb 25 20
Electric kettle 200 180
Electric drill 500 300
80J
Answer here
Answer here
Answer here
Complete the table
light electrical kinetic potential sound
The figure below shows a car with an electric motor.
The car is moving along a flat road.
(a) (i) Use the correct answers from the box to complete each sentence.
The car’s motor transfers _______________________ energy
into useful _______________________ energy as the car moves.
Some energy is wasted as _______________________ energy.(3)
(ii) What happens to the wasted energy?
______________________________________________________________
______________________________________________________________(1)
4 marks)
Answer here
Answer hereAnswer here
Answer here
Fill the gaps.
Every type of packaged food will tell you how much chemical energy it contains. Remember we always use the units Joules for energy. Often there will be two values. Energy contained in 100g of the food and the energy contained in one portion of the food
Energy per 100g = 985kJEnergy per portion = 435kJ
Energy in the home Read the information
Answer here
Answer here
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Strawberry Trifle
Answer here
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726 kJ
Answer here
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Answer here
538kJ
Find your 5 favourite foods or drinks, and fill in the table below an example has been given in the first set of boxes to help you
Use your table on the previous slide to answer the following questions
1. Which of your foods had the most energy per 100g?
2. Which of your foods had the most energy per portion?
3. Which had the least amount of energy per 100g?
4. What do you think this chemical energy is transferred into (hint, what does a human need energy for)?
5. Which is your favourite food?
6. What other information can you see on the food label?
Answer here
Answer here
Answer here
Answer here
Answer here
Answer here
Answer the questions
EfficiencyIn the U.K., the government will give you a grant to have your house insulated. This means it is more difficult for heat to leave your house.Do you think this should
be done for all people in the UK or just certain groups like the elderly? Use the next slide to explain why
Read the information
Key Words – Tool Box
Thermal, Insulation, Heat loss, Conduction, Dissipated, Efficiency, Sankey Diagram, Joules, Transfer
Write your answer here. The box will expand as you type.
Do you think the government should pay for all people to have insulation in the UK, or just certain groups like the elderly?
Power
Terms that often get confused are energy and power.
Energy is the ability to do work. It is given the unit Joule (J)
Power is the rate energy is used. It is given the unit Watts (W) or often kilowatts (kW) is used. The term kilo means x 1000.
Therefore 1kW is the same as 1000 Watts
Read the information
Both these planes are about the same mass but the jet has more powerful engines.
Power is the rate at which work is done. A more powerful engine therefore does work (i.e. transfers energy) faster than a less powerful engine.
This means that chemical energy in the fuel can be transferred to kinetic energy faster so it will have greater acceleration and a higher top speed.
Read the information
Drag and drop each device to order them from what you think is the most power to the least power.
The power ratings are at the side, change your list to display the correct order from highest power to lowest power.
TV 0.120 kWKettle 1.800 kWFridge 0.035 kWIron 1.100 kWLaptop 0.050 kWXbox one 0.150 kW
Research the career of Astrophysicist Sarah Cruddas
Answer the questions:
Who is she?
What does she do?
When did she do it?
Where did she do it?
Why did she do it?
Check your understanding
Has your understanding changed?
Put an X in the boxes to show how much you understand on the following topics
Topic
Types of energy
Energy stores and transfers
Energy efficiency
Power