EXPECTATIONS 1.Dont talk when the teacher is talking 2.Respect
others in the classroom 3.Ask questions if you are unsure
4.Complete all homework on time
Slide 4
KEYWORDS: resultant, Newton, Acceleration, mass, stationary
KEYWORDS: resultant, Newton, Acceleration, mass, stationary
Calculate the forces acting on an object ALL Calculate the
resultant force acting on an object MOST Describe the effect of a
resultant force on stationary and moving objects SOME Use the
equation F=m x a to calculate the forces on an object Starter Find
the definition of a resultant force using the textbook
Slide 5
Forces A force can be simply described as either a push or a
pull. Forces are measured in Newtons (N) 1 Newton is the force
required to accelerate a 1kg mass by 1m/s. LO: calculate the forces
acting on an object Watch the following video and think about the
forces that are occurring between the car and the wall
http://www.youtube.com/w atch?v=6dI5ewOmHPQ
Slide 6
Forces between objects When two objects push or pull on each
other, they exert equal and opposite forces on one another e.g. you
are all pushing down on the floor, but the floor is also pushing up
on you.if it didnt youd fall straight through the floor! LO:
calculate the forces acting on an object
Slide 7
Resultant force If you have multiple forces acting on an
object, you can replace them with one single force that has the
effect of all the other forces combined together. This single force
is called the resultant force LO: calculate the forces acting on an
object
Slide 8
Calculating the resultant A rocket produces a thrust of 2000N.
It has a weight of 1000N. What is the resultant force acting on the
rocket? LO: calculate the forces acting on an object
Slide 9
Calculating the resultant A rocket producing a resultant force
of 1000N hits a wall, causing it to come to a stop. What force does
the wall exert on the rocket and the rocket exert on the wall.
Explain the reasoning for your answer. LO: calculate the forces
acting on an object
Slide 10
Calculating the resultant A car of weight 5000N produces a
driving force of 2000N. It experiences friction force from the
ground of 500N and air resistance of 300N. What are the horizontal
and vertical resultant forces acting on the car? LO: calculate the
forces acting on an object
Slide 11
Rules for calculating the resultant 1.Forces that act in the
same direction can be added together 2.Forces that act opposite to
each other must be taken away 3.Forces that act vertically and
horizontally CAN NOT be added and taken away from each other and
MUST be considered separately. LO: calculate the forces acting on
an object
Slide 12
Task Complete the (very simple!) worksheet on calculating
resultants and stick it into your books! LO: calculate the forces
acting on an object
Slide 13
10 8 6 4 2 0 10 Minutes Start Timer State what happens when an
object exerts a force on another object Describe what is meant by a
resultant force A car weighs 5000N and has a driving force of
2000N. It experiences a resisting force of 2000N. What is the
horizontal and vertical resultant force acting on the car?
Slide 14
Effects of forces 1 LO: calculate the forces acting on an
object The resultant force on a stationary (not moving) object is
zero! If a resultant force is applied to an object, it will
accelerate in the direction of the force
Slide 15
Effects of forces 2 LO: calculate the forces acting on an
object If an object is moving with constant speed, the resultant
force on it is zero If a resultant force is applied to a moving
object, it will accelerate in the direction of the force
Slide 16
Task LO: calculate the forces acting on an object Stationary
object Moving object Zero resultant force Non-zero resultant
force
Slide 17
Calculating forces F = force (N) m = mass (kg) a = acceleration
(m/s 2 ) LO: calculate the forces acting on an object F = m x a m x
a F
Slide 18
Example 1 A car of mass 400kg is accelerating at 5m/s 2. What
is the driving force produced by the engine? LO: calculate the
forces acting on an object
Slide 19
Example 2 A novice skier is being pulled along a horizontal
section of a nursery slope. Given that her acceleration of 1.3m/s 2
is provided by a force of 70N, calculate her mass. LO: calculate
the forces acting on an object
Slide 20
Example 3 A man pushes a car with a force of 200N along a
straight horizontal road. He manages to accelerate the car by
0.1m/s. Find the mass of the car. LO: calculate the forces acting
on an object
Slide 21
Task Complete the questions on calculating forces on the
worksheet, showing your working out for each one. Stick the
worksheet into your book when you are done. LO: calculate the
forces acting on an object
Slide 22
10 8 6 4 2 0 10 Minutes Start Timer What is the unit of
measurement for acceleration? Describe the forces acting on an
arrow that has been fired from a bow and is moving at constant
speed. A car has a mass of 500kg. Calculate the force required to
accelerate the car by 2m/s.
Slide 23
KEYWORDS: distance-time graph, distance Velocity-time graph,
acceleration, velocity KEYWORDS: distance-time graph, distance
Velocity-time graph, acceleration, velocity Understand how to draw
and interpret graphs of motion ALL Draw distance and velocity-time
graphs MOST Describe the motion of an object using distance and
velocity-time graphs SOME Calculate particular quantities using
distance and velocity-time graphs Starter Brain teaser!
Slide 24
Graphs of motion Graphs of motion are a visual representation
of the motion of a body They can either show the change in
displacement or change in velocity of an object LO: understand how
to draw and interpret graphs of motion
Slide 25
Can you draw Mr C cycles into work. The journey takes him 15
minutes (900s) and is a total distance of 3km (3000m). We will try
to represent his journey using a graph LO: understand how to draw
and interpret graphs of motion
Slide 26
Slide 27
Can you draw 1.Mr C cycles to the first traffic light, a
distance of 500m away. It takes him 180 seconds to do this. 2.He
waits at the traffic lights for 120 seconds while the light is red
3.When the light turns green, he cycles for 2000m without stopping.
This takes him 5 minutes to do. 4.After 2000m, Mr C has to stop at
another traffic light. He waits for 180 seconds. 5.Realising that
he is about to be late, he sprints the last 500m in 120 seconds.
LO: understand how to draw and interpret graphs of motion
Slide 28
Practical Creating graphs of motion Aim: To create your own
graphs of motion Equipment: Ruler Stopwatch Maggot Method: 1.Place
your maggot on the ruler 2.Allow it to crawl along 3.Measure the
distance it travels every 30s 4.Record the data in an appropriate
table 5.Draw a displacement-time graph for the motion. Make sure
the distance is in metres!!! LO: understand how to draw and
interpret graphs of motion
Slide 29
Slide 30
Mini-plenary 1.Usain Bolt ran the 100m race in London 2012 in
approximately 9.6 seconds. He ran the first 20m in approximately
2.7 seconds after accelerating and running the final 80m in 6.9
seconds. It took him 20 metres to come to a stop, which he covered
in 5 seconds. Draw a distance-time graph to show this journey.
2.Explain what a horizontal line on a distance-time graph
represents Extension: What do you think the steepness of a line on
a distance-time graph represents? LO: understand how to draw and
interpret graphs of motion
Slide 31
Using distance-time graphs How steep the line is (the gradient)
on a distance-time graph tells you the speed that an object is
moving The steeper the line, the faster something is moving Speed
is measured in m/s LO: understand how to draw and interpret graphs
of motion
Slide 32
Calculating the gradient Gradient = LO: understand how to draw
and interpret graphs of motion Change in y Change in x Gradient = y
x Lets have a go at working out the speed that Mr C was travelling
at during his journey to school!
Slide 33
One last definition LO: understand how to draw and interpret
graphs of motion Two cars are travelling on a road in opposite
directions. One is travelling east at 20m/s and the other is
travelling west at 20m/s. Their speeds are exactly the same.
However, their velocitys are different. What do you think their
velocitys are? Velocity is the speed of an object in a given
direction. Two objects can have the same speed, but very different
velocities
Slide 34
Task 1.Complete the summary sheet on distance-time graphs and
stick it into your book 2.Complete the exam questions on
distance-time graphs LO: understand how to draw and interpret
graphs of motion
Slide 35
Homework Create a graph of motion of your journey into school!
It doesnt have to be accurate, an estimate will do! LO: understand
how to draw and interpret graphs of motion
Slide 36
What do you know? I understood everything! I understood most of
todays work I need more help to understand todays work LO:
understand how to draw and interpret graphs of motion
Slide 37
KEYWORDS: distance-time graph, distance Velocity-time graph,
acceleration, velocity KEYWORDS: distance-time graph, distance
Velocity-time graph, acceleration, velocity Understand how to draw
and interpret graphs of motion ALL Draw distance and velocity-time
graphs MOST Describe the motion of an object using distance and
velocity-time graphs SOME Calculate particular quantities using
distance and velocity-time graphs Starter Brain teaser!
Slide 38
Graphs of motion II Last lesson, we learnt how to draw
distance-time graphs This lesson, we will learn how to draw
velocity-time graphs LO: understand how to draw and interpret
graphs of motion
Slide 39
Can you draw Mr C has brought himself a slick new ride! He has
also moved house and is now living in the leafy suburbs. His
journey takes him 1200 seconds, his top speed is 50m/s and his
lowest is -30m/s. Lets plot his journey into school on a
velocity-time graph LO: understand how to draw and interpret graphs
of motion
Slide 40
Slide 41
Can you draw 1.Mr C leaves his house. He is happily driving
along on country roads at a steady speed of 30m/s for two minutes
2.Doh! Hes forgotten his lunch. He turns round and drives back at
30m/s for two minutes. He is at home for 60s. 3.Back on the road,
Mr C drives at 30m/s for 300s 4.Now on the motorway, Mr C is able
to drive at 50m/s, which he does for 5mins 5.Coming off the
motorway, he stops at a traffic light for 120s 6.Realising he is
going to be late, he steadily increases his speed for the next 180
seconds from 0 to 50m/s. He arrives JUST on time! LO: understand
how to draw and interpret graphs of motion
Slide 42
Task Answer the following questions in your books: 1.What does
a horizontal line on a velocity-time graph represent? 2.How do you
know if an object has stopped by looking at the velocity-time
graph? 3.How can you tell if an object is accelerating using a
velocity time graph? 4.Draw the velocity-time graph for the
following journey: 0-10s = 50m/s 10-25s = 0m/s 25-50s = 60m/s
50-80s = acceleration to 80m/s LO: understand how to draw and
interpret graphs of motion
Slide 43
Acceleration Acceleration is the change in speed of a body over
a given amount of time LO: understand how to draw and interpret
graphs of motion
Slide 44
Acceleration Acceleration can be calculated using the following
equation: LO: understand how to draw and interpret graphs of motion
Acceleration = Change in velocity Time taken Final velocity initial
velocity Time taken Acceleration = v - u t a = a = acceleration
(m/s 2 ) v = final velocity (m/s) u = initial velocity (m/s) t =
time (s)
Slide 45
Example 1 A car accelerates from a velocity of 10m/s to a
velocity of 25m/s in 15 seconds. What is the acceleration of the
car? LO: understand how to draw and interpret graphs of motion
Slide 46
Example 2 A runner starts at rest and accelerates to a top
speed of 10m/s. If he does this in 2 seconds, what is his
acceleration? LO: understand how to draw and interpret graphs of
motion
Slide 47
Example 3 A train accelerates at 2m/s for 30 seconds. If its
initial velocity was 10m/s, calculate what the final velocity will
be after 30 seconds. LO: understand how to draw and interpret
graphs of motion
Slide 48
Task 1.What is the acceleration of a car that starts at rest
and reaches a top speed of 50m/s in 25 seconds? 2.A plane starts at
rest. It takes 8 seconds to take off and accelerates at a constant
rate of 10m/s. What is the final take- off velocity of the
aircraft? 3.A runner starting at rest reaches a speed of 11m/s in
2.2 seconds during the drive phase of his 100m sprint. What is his
acceleration during this phase? Assuming that his speed remains
constant for the rest of the race, sketch the velocity- time graph
for his journey 4.A car accelerates at 5m/s for 12 seconds,
reaching a final velocity of 80m/s. What was the cars initial
velocity before it started accelerating? LO: understand how to draw
and interpret graphs of motion
Slide 49
How are they linked? The gradient of a velocity time graph
represent the acceleration of an object! Go back and calculate the
acceleration of Mr C in the final part of his journey LO:
understand how to draw and interpret graphs of motion Gradient =
Change in y Change in x Gradient = y x
Slide 50
How are they linked? The area under a velocity-time graph is
the total distance that the object has travelled Go back and
calculate the total distance Mr C travels to get to work LO:
understand how to draw and interpret graphs of motion
Slide 51
Task Answer the exam questions on velocity-time graphs. Stick
the questions into your books when you are done. LO: understand how
to draw and interpret graphs of motion
Slide 52
10 8 6 4 2 0 10 Minutes Start Timer What is the difference
between speed and velocity? Describe how you would calculate speed
from a velocity-time graph Describe how you would calculate total
distance travelled from a velocity-time graph
Slide 53
KEYWORDS: force, braking, profile, stopping distance, thinking
distance, braking distance KEYWORDS: force, braking, profile,
stopping distance, thinking distance, braking distance Understand
the factors that affect the stopping distance of a car ALL state
the definitions of stopping, braking and thinking distance MOST
Describe factors that will affect the stopping distance of a car
SOME explain why driving whilst on the phone is very dangerous
Starter Make a spider diagram of the factors that would affect the
maximum speed of a car
Slide 54
LO: understand the factors that affect the stopping distance of
a car FACTORS THAT AFFECT TOP SPEED
Slide 55
Streamlining LO: understand the factors that affect the
stopping distance of a car Most of the resistance forces that act
on a car are due to air resistance. Streamlining a car will
increase the top speed, even if the engine is giving the same power
output
Slide 56
Stopping distance The stopping distance of a car is the minimum
distance that a car can safely stop in Stopping distance = thinking
distance + braking distance LO: understand the factors that affect
the stopping distance of a car
Slide 57
Thinking distance The thinking distance is the distance
travelled by the vehicle in the time it takes for the driver to
react LO: understand the factors that affect the stopping distance
of a car alcohol other drugs and some medicines tiredness
distractions, such as mobile phones speed
Slide 58
Stopping distance The stopping distance is the distance
travelled by the vehicle during the time the braking force acts LO:
understand the factors that affect the stopping distance of a car
weather condition of tyres/brakes condition of road speed
Slide 59
Typical stopping distances What effect would factors such as
drugs, alcohol, tiredness, higher speed, adverse weather, poor road
conditions or worn out breaks have on these stopping distances? LO:
understand the factors that affect the stopping distance of a
car
Slide 60
Braking force LO: understand the factors that affect the
stopping distance of a car Which of these would need the bigger
force to stop if the stopping distance remained the same? Why?
Slide 61
10 8 6 4 2 0 10 Minutes Start Timer What is the definition of
stopping distance? Explain why poor weather and worn out brakes
would both lead to an increase in braking distance Explain, using
the equation F=mxa, why you would need a higher breaking force to
stop a lorry compared to a mini
Slide 62
Practical Reaction times LO: understand the factors that affect
the stopping distance of a car Aim: To investigate the effect of
distractions on reaction time Method: 1.Work in groups of three
2.Use a stopwatch to measure your reaction times with no
distractions 3.Repeat the experiment with one person acting as the
distractor 4.Repeat the experiment a number of time to get an
average reaction time with and without distractions
Slide 63
Practical Reaction times LO: understand the factors that affect
the stopping distance of a car Write a conclusion for your
experiment based on your results A/A* - Write an evaluation for the
experiment and how it could be improved
Slide 64
QWC Practice A local authority is worried about the number of
road deaths occurring in the area. They have imposed a ban on
mobile phones while driving, imposed a speed limit of 30mph and
installed speed cameras. Explain how the changes may lead to fewer
people being hit by cars. 5-6 marks criteria: Knowledge of accurate
information appropriately contextualised Detailed understanding,
supported by relevant evidence and examples Answer is coherent and
in an organised, logical sequence, containing a wide range of
appropriate or relevant specialist terms used accurately The answer
shows almost faultless spelling, punctuation and grammar. LO:
understand the factors that affect the stopping distance of a
car
Slide 65
Slide 66
KEYWORDS: terminal velocity, force, Resistance, streamline,
weight KEYWORDS: terminal velocity, force, Resistance, streamline,
weight Understand what is meant by terminal velocity ALL state the
definition of terminal velocity MOST Describe the motion of an
object moving through a fluid SOME explain the forces that are
acting on an object when it is travelling at terminal velocity
Starter Answer the exam question on stopping distances
Slide 67
Slide 68
Slide 69
What is happening? LO: understand what is meant by terminal
velocity The graph below shows the velocity-time profile for a
skydiver falling through the air. Discuss with the people on your
pod what you think is happening and why. Think about the forces
that are involved at each stage
Slide 70
Moving in a fluid LO: understand what is meant by terminal
velocity Lets think about what happens when an object moves through
a fluid by considering a skydiver When the skydiver FIRST jumps out
of the aircraft, gravity causes him to accelerate. The acceleration
is a constant so the line on v-t graph will have an unchanging
steepness at the beginning
Slide 71
Moving in a fluid LO: understand what is meant by terminal
velocity As the speed of the skydiver increases, the air resistance
on him increases. The increased air resistance causes his
acceleration to decrease. However, his velocity is still increasing
i.e. hes speeding up slower than before, but hes NOT slowing
down.
Slide 72
Moving in a fluid LO: understand what is meant by terminal
velocity After a certain amount of time, the weight of the skydiver
and the air resistance on the skydiver will be balanced. At this
point, the skydiver will be moving at a constant velocity. This is
the MAXIMUM velocity it is possible for him to move with and is
known as the TERMINAL VELOCITY.
Slide 73
Moving in a fluid LO: understand what is meant by terminal
velocity The process that we have just considered is relevant for
ANY object that is moving in a fluid e.g. a car driving along a
road, a plane flying at 2000ft, a submarine underwater etc.
Slide 74
Moving in a fluid LO: understand what is meant by terminal
velocity The factors that will increase/decrease the terminal
velocity of an object are: The driving force that the object can
generate How streamlined the object is The fluid that the object is
travelling through
Slide 75
Task LO: understand what is meant by terminal velocity Draw a
comic strip to explain how the velocity of a skydiver will change
as they fall through the sky. Use the following keywords in your
comic strip: Gravity, weight, air resistance, accelerate, resultant
force, zero A/A* task: Extend your comic strip to the point where
the skydiver opens their parachute. What effect will this have on
the force on the skydiver and their terminal velocity?
Slide 76
Calculating weight LO: understand what is meant by terminal
velocity The weight of an object is the force that acts on an
object due to gravity. It can be calculated using the following
equation: W = m x g W = weight (Newtons) M = mass (kg) g =
gravitational field strength (N/kg) g has a value of 9.81 on
earth
Slide 77
Task LO: understand what is meant by terminal velocity Use the
equation to find the weight of the following objects on earth: 1.A
car of mass 2000kg 2.A person of mass 70kg 3.A football of mass
500g 4.A tennis ball of mass 0.1kg 5.A building of mass 1000,000kg
g is 9.81N/kg on earth The gravitational field strength on the moon
is 1.6N/kg. Recalculate the weight of the above objects on the
moon
Slide 78
Practical - Parachutes LO: understand what is meant by terminal
velocity Aim: To make the best possible parachute using a very
limited set of resources Equipment: Two plastic bags Sellotape 40cm
of string Polystyrene cup Your parachutes will be holding a 200g
mass in the cup. Whichever parachute takes the longest to fall down
the steps will be the winner!
Slide 79
Plenary LO: understand what is meant by terminal velocity
Answer the exam questions on terminal velocity. Stick them into
your books when you are done.
Slide 80
Plenary LO: understand the link between force and extension of
an object Write down that the questions should be that go with
these answers: 1.It tells you the speed that a molecule is
travelling with 2.You can calculate it by working out the total
area underneath the line 3.It is the maximum velocity that an
object is able to achieve 4.It is the one force that gives the same
effect as all the other forces acting on an object 5.It is the
distance that an object moves when the brake force is applied 6.It
is sum of the thinking distance and the braking distance of an
object
Slide 81
KEYWORDS: force, Hookes law, extension, elastic limit, plastic
KEYWORDS: force, Hookes law, extension, elastic limit, plastic
Understand the link between force and extension of an object ALL
state the effect of forces on an object MOST Describe how the shape
of an object is changing when a force is applied to it SOME
Calculate the extension of an object when a particular force is
applied Starter What is the question?
Slide 82
Changing shape LO: understand the link between force and
extension of an object When a force is applied to an object, it may
accelerate. However, a second effect that the force may cause is a
change in shape of the object
Slide 83
Stretching objects LO: understand the link between force and
extension of an object When an object is stretched, it stores
elastic potential energy. Some objects are better at storing this
energy than others. Which of the materials on your pod is better at
storing elastic potential energy?
Slide 84
Practical - Springs Aim: To determine a relationship between
force applied and extension of a spring Method: Measure the initial
length of your spring when unstretched Attach the spring to a clamp
stand Put a 10g weight onto the spring Measure the extension of the
spring Repeat the experiment adding 10g each time Measure your
results on a results table Plot your results when you are finished
and draw a line of best fit LO: understand the link between force
and extension of an object
Slide 85
Slide 86
Conclusion Using your graph, what can you conclude about the
relationship between force and extension? Using your graph,
calculate the extension when the force applied is: 23g 42g 70g LO:
understand the link between force and extension of an object
Slide 87
Material properties The same process that you have just done is
done on all materials to find out their characteristics Most
materials have a range where the force and extension are
proportional LO: understand the link between force and extension of
an object The constant gradient here shows us that the force and
extension are proportional
Slide 88
Material properties Beyond a point, the material will start to
show plastic behaviour. A small increase in force will give a large
increase in extension. The deformation will be irreversible (the
material will not go back to the original shape when the force is
taken away) LO: understand the link between force and extension of
an object Beyond the proportional limit, the material shows plastic
behaviour. The extension is now much harder to predict
Slide 89
Real world application Knowing how materials change shape under
force is essential to most aspects of university. The flexing of
aircraft wings can dramatically change the lift generated. It also
needs to be within limits to make sure the wings dont break off!
LO: understand the link between force and extension of an
object
Slide 90
Hookes Law Hookes law states that: The extension of an object
is directly proportional to the force that is applied to it
provided that the limit of proportionality is not exceeded LO:
understand the link between force and extension of an object
Slide 91
Hookes Law Hookes law can be written as: F = k x e LO:
understand the link between force and extension of an object F =
Force (N) k = spring constant (N/m) e = extension (m)
Slide 92
Task Answer the following questions in your exercise books:
1.Calculate the spring constant for the spring that you did the
experiment with 2.A spring is loaded with a force of 50N four
times. The spring shows extensions of 0.23m, 0.25m, 0.25m and
0.24m. Calculate the spring constant for this spring 3.For the
spring in the question above, calculate the force when the
extension of the spring is 100cm. 4.A second spring is loaded with
100N. It shows an extension of 60cm. What is the difference between
the spring constants of the two springs? 5.What would be the force
required to extend the second spring by 0.45m? LO: understand the
link between force and extension of an object
Slide 93
10 8 6 4 2 0 10 Minutes Start Timer What does Hookes law state?
Calculate the force required to extend a spring with spring
constant 32N/m by 2 metres. Explain what is meant by the term
proportional limit
Slide 94
Homework You will have a test on next lesson on everything that
you have learnt so far for this topic. Your homework is to revise
in preparation for this test. LO: understand the link between force
and extension of an object
Slide 95
KEYWORDS: work done, force, energy, Energy transferred
KEYWORDS: work done, force, energy, Energy transferred Understand
how energy can be transferred ALL state the definitions of work
MOST Describe the link between work done and energy transferred
SOME Calculate the work done by an object Starter Make a spider
diagram of all the different forms of energy that you know
Slide 96
FORMS OF ENERGY
Slide 97
What is work? LO: understand how energy can be transferred An
object is said to have done WORK when it transfers (uses)
energy
Slide 98
Calculating work LO: understand how energy can be transferred
The work done by an object is equal to the amount of energy that it
transfers Work done = force x distance W = f x d W = work done(J) f
= force (N) d = distance(m)
Slide 99
Example 1 An object of weight 40N is raised by a height of
0.4m. Calculate the work done in raising the object. LO: understand
how energy can be transferred
Slide 100
Example 2 2000J of energy is transferred by a sprinter as he
runs a distance of 100m. Calculate the force that is exerted by the
sprinter as he is running. LO: understand how energy can be
transferred
Slide 101
Example Questions 1.What is the definition of work done? 2.What
is the unit for energy? 3.The engine of a car exerts a force of
750N. How much energy would be transferred by the engine if the car
moved a distance of 100m? 4.An object of weight 50N is raised by a
height of 200cm. What is the work done in raising the object?
5.700J of energy is used by a person to move a distance of 10m.
What is the force exerted by the person as they walk the distance?
6.Object A has a weight of 200N. Object B has a weight of 350N. If
1000J of energy is used to raise each object, which object will
gain the most height? LO: understand how energy can be
transferred
Slide 102
Calculating power LO: understand how energy can be transferred
Power is the amount of work done/energy transferred in a given time
Power = work done / time P = W / t P = power (W) W = work done (J)
t = time (s)
Slide 103
Example 1 An object of weight 700N is raised by a height of 2m
in a time of four seconds. Calculate the work done in raising the
object and the power. LO: understand how energy can be
transferred
Slide 104
Practical - Power Aim: To calculate the power required for you
to run up the stairs Method: 1.Work out your weight (your mass x
9.81) 2.Run up the stairs as fast as you can 3.Work out the energy
transferred as you run up the stairs (your weight x height of
stairs) 4.Work out your power (work done / time) The boy and girl
who have the highest power will win 40vivos each! LO: understand
the structure of an atom
Slide 105
Example Questions 1.A car engine transfers 3000J in 20 seconds.
What is the power generated by the engine? 2.400J of energy is
transferred in raising an object in 1 minute. What is the power?
3.A kettle has a power rating of 2000W. How much work is done by
the kettle in boiling water in 40 seconds? 4.A student of weight
500N transfers 2000J whilst running up some stairs. She reaches the
top of the stairs in 3 seconds. How high are the stairs and what is
her power? 5.A sprinter can generate 150W whilst running. If he
transfers 450J of energy, how long has he been running for? LO:
understand how energy can be transferred
Slide 106
10 8 6 4 2 0 10 Minutes Start Timer What are the definitions of
work done and Power Calculate the power of a car that transfers
1000J in 10 seconds A Kettle has a power rating of 500W and a
toaster of 300W. What is the difference in the amount of energy
they transfer in 10 seconds?
Slide 107
KEYWORDS: work done, gravitational potential energy KEYWORDS:
work done, gravitational potential energy Understand the nature of
gravitational potential energy ALL state the definitions of GPE
MOST Calculate the GPE of objects SOME Explain how GPE can be
transferred into other forms of energy
Slide 108
Gravitational Potential Energy Any object that is raised above
the ground will have gravitational potential energy LO: understand
the nature of gravitational potential energy
Slide 109
Gravitational Potential Energy GPE = mass x LO: understand the
nature of gravitational potential energy Gravitational Field
strength x height GPE = m x g x h GPE = gravitational potential
energy (J) m = mass (kg) g = gravitational field strength (N/kg) h
= height (m)
Slide 110
Example 1 An object of mass 10kg is raised by a height of 20m.
What is the gravitational potential energy of the object? LO:
understand the nature of gravitational potential energy
Slide 111
Example 2 An object gains gravitational potential energy of
300J. If the mass of the object is 3kg, what is the height that the
object has been raised? LO: understand the nature of gravitational
potential energy
Slide 112
Practical - GPE Aim: To calculate the gravitational potential
energy of a bouncy ball Method: 1.Measure the initial height of the
ball 2.Calculate the initial gravitational potential energy 3.Drop
the ball and measure the height it reaches at each successive
bounce for 5 bounces 4.Calculate the gravitational potential energy
of the ball for each bounce 5.Repeat the process on a different
surface LO: understand the nature of gravitational potential
energy
Slide 113
Practical - GPE Plot a line graph of your results (GPE on the y
axis and bounce on x axis). Why does the gravitational potential
energy reduce each time the ball bounces? Where is the energy
transferred? What is the best surface to bounce the ball on? How do
you know? LO: understand the nature of gravitational potential
energy
Slide 114
10 8 6 4 2 0 10 Minutes Start Timer What is the equation to
calculate GPE? What is the GPE of an object that has a mass of 300g
that is raised by 1m? An astronaut jumps up 0.5m on the moon.
Explain why the amount on GPE he gains is less than if he jumped
the same distance on earth
Slide 115
KEYWORDS: work done, kinetic energy Understand the nature of
kinetic energy ALL state the definitions of kinetic energy MOST
Calculate the kinetic energy of objects SOME Explain the factors
that will affect the kinetic energy of an object
Slide 116
Kinetic energy All objects that are moving have kinetic energy!
LO: understand the nature of kinetic energy
Slide 117
Kinetic energy KE = x m x v LO: understand the nature of
kinetic energy KE = kinetic energy (J) m = mass (kg) v = velocity
(m/s)
Slide 118
Example 1 An object has a mass of 2kg and is moving with a
velocity of 5m/s. What is the kinetic energy of the object? LO:
understand the nature of kinetic energy
Slide 119
Example 2 An object of mass 300g has 600J of kinetic energy.
How fast is the object moving? LO: understand the nature of kinetic
energy
Slide 120
Example questions 1.What is the equation that is used to
calculate the kinetic energy of an object? 2.Calculate the kinetic
energy of an object of mass 500g that is moving with a velocity of
20m/s 3.A car of mass 500kg is a moving with a velocity of 10m/s.
It accelerates to a velocity of 15m/s. What is the KE of the object
before and after it accelerates? 4.A sprinter has kinetic energy of
1000J and a mass of 68kg. How fast is the sprinter running? 5.A
ball of mass of 0.5kg is dropped from a height of 2m. Assuming that
all of the GPE is transferred to KE, what will be the velocity of
the ball when it hits the ground? LO: understand the nature of
kinetic energy
Slide 121
Slide 122
Practical Kinetic energy Aim: To calculate the kinetic energy
of objects Method: 1.Time how long it takes for the car to move
down the slope 2.Calculate the velocity of the car using speed =
distance/time 3.Calculate the KE of the car 4.Repeat the experiment
to find an average 5.Repeat the experiment on a different surface
LO: understand the nature of kinetic energy
Slide 123
Practical Kinetic energy Make a conclusion for the experiment
explaining on which surface the car had the most kinetic energy.
Use your results from the experiment to back up your conclusion.
LO: understand the nature of kinetic energy
Slide 124
Plenary Add to the spider diagram that you made at the
beginning of the lesson. Add everything that you have learnt about
energy, work, power, GPE and KE. LO: understand the nature of
kinetic energy
Slide 125
KEYWORDS: momentum, mass, Velocity, conservation of momentum
KEYWORDS: momentum, mass, Velocity, conservation of momentum
Understand what is meant by momentum ALL state the definition of
momentum MOST perform calculations for momentum SOME Explain what
is meant by the conservation of momentum Starter Bingo
Slide 126
BINGO
Slide 127
Momentum ALL MOVING OBJECTS HAVE MOMENTUM! LO: understand what
is meant by momentum
Slide 128
Momentum P = m x v LO: understand what is meant by momentum P =
momentum (kgm/s) m = mass (kg) v = velocity (m/s)
Slide 129
Example question 1 An object of mass 300g is moving with
velocity of 5m/s. What is its momentum? LO: understand what is
meant by momentum
Slide 130
Example question 2 An object has momentum of 50kgm/s. If the
object has a mass of 25kg, what is its velocity? LO: understand
what is meant by momentum
Slide 131
Example questions 1.What is the momentum of a bullet of mass
50g travelling at 300 m/s? 2.What is the momentum of a dog (mass 12
kg) fired out of a canon at 120 m/s? 3.Calculate the momentum of a
65 kg sprinter when travelling at 9.5 ms -1. 4.Calculate the
velocity of a car of mass 700 kg that has the same momentum as the
sprinter in Q3 5.A body has a mass of 2.5 kg. Calculate: Its
momentum when it has a velocity of 3.0 m/s Its velocity when it has
a momentum of 10.0 kgm/s LO: understand what is meant by
momentum
Slide 132
Conservation of momentum In a closed system, the total momentum
before an event and the total momentum after an event are the same.
This is called conservation of momentum. Events you may be asked
about in your exams are: Collisions Explosions LO: understand what
is meant by momentum
Slide 133
Example 1 A railway engine of mass 800kg travelling at 5m/s
collides with and becomes attached to a truck of mass 200kg
travelling at 2m/s. Calculate the speed of the truck and engine
after the collision LO: understand what is meant by momentum
Slide 134
Example 2 A 0.5kg trolley is pushed at a velocity of 1.2m/s
into a stationary trolley of mass 1.5kg. The two trolleys stick to
each other after the impact. Calculate: The momentum of the 0.5kg
trolley before the collision The velocity of the two trolleys
straight after the impact LO: understand what is meant by
momentum
Slide 135
Task Answer the exam questions on momentum and energy. Stick
the questions into your book when you are done! LO: understand what
is meant by momentum
Slide 136
Explain how safety features on a car work ALL State some car
safety features MOST Describe the energy transfers during braking
SOME Explain how safety features on a car work Starter Make a
spider diagram of all the safety features that you can think of on
a car
Slide 137
Starter LO: explain how safety features on a car work Car
safety features
Slide 138
Brakes and crumple zones Brakes and crumple zones are two of
the main safety features on a car LO: explain how safety features
on a car work
Slide 139
Brakes and crumple zones Both features work by transferring
kinetic energy into other forms. What energy transfers take place
in each of these features? LO: explain how safety features on a car
work
Slide 140
Brakes and crumple zones Task: Write a brief description of how
brakes and crumple zones work to reduce the risk of serious harm to
car passengers LO: explain how safety features on a car work
Slide 141
To understand static electricity ALL State some methods of
creating static electricity MOST Describe the structure of an atom
SOME Explain what happens when static electricity is created
Slide 142
Structure of an atom LO: understand static electricity All
matter is made up of atoms However, an atoms is NOT the smallest
unit of matter like you might have been previously taught Atoms of
themselves made of smaller particles
Slide 143
What is an atom made up of? LO: understand static electricity
Protons Positively charged particles found inside the nucleus
Neutrons Neutral particles found inside the nucleus Electrons
Negatively charged particles that orbit the nucleus
Slide 144
Structure of an atom LO: understand static electricity
Slide 145
Practical Static Electricity LO: understand static electricity
Aim: To create static electricity! Method: Use the equipment on
your pod to create static electricity! Is the static electricity
that you create the same with each piece of equipment or are there
some differences?
Slide 146
Static electricity by friction LO: understand static
electricity When you rub one of the rods with the cloths, you
create static electricity. This happens in one of two ways. For the
polythene rod, the dry cloth transfers electrons TO the surface of
the rod and gives it a negative charge
Slide 147
Static electricity by friction LO: understand static
electricity When you rub one of the rods with the cloths, you
create static electricity. This happens in one of two ways. For the
perspex rod, the dry cloth transfers electrons away from the
surface of the rod. This gives it a positive charge
Slide 148
Static electricity rules LO: understand static electricity
1.Like (The same) charges attract 2.Unlike (The opposite) charges
repel
Slide 149
Knowledge check LO: understand static electricity Copy the true
sentences and change the false sentences to make them true:
1.Crumple zones help to absorb the gravitational potential energy
of a car 2.Like charges attract 3.Opposite charges attract 4.A
polythene rod becomes negatively charged if rubbed by a dry cloth
5.Atoms are made of protons, neutron and smurfs
Slide 150
To understand how to create electrical circuits ALL State the
difference between series and parallel circuits MOST Identify key
circuit components SOME Perform calculations to find the current in
a circuit
Slide 151
Key definitions When considering electricity, we will usually
use three key terms: 1)Current: This is the flow of electric
charges around a circuit. The size of the current is dependent on
the rate of flow of electric charges 2)Potential Difference
(Voltage): The potential difference between two points is the work
done per unit charge between two points 3)Resistance: This is the
resistance to the flow of electrons around a circuit LO: Understand
how to create electrical circuits
Slide 152
Calculating current I = Q/t LO: Understand how to create
electrical circuits I = Current (Amps, A) Q = Charge (Coulombs, c)
t = Time (s)
Slide 153
Example question 1 Calculate the current when 4C passes a point
in 8 seconds LO: Understand how to create electrical circuits
Slide 154
Example question 2 An ammeter is records a current of 8A.
Calculate how much charge is passing through the ammeter in 10
seconds. LO: Understand how to create electrical circuits
Slide 155
Task 1.What is the current when 20C of charge pass through an
ammeter in 2minutes? 2.A battery can produce 20A of current. How
much charge does it discharge in 30s? 3.Another battery can produce
a charge of 30A. How long will this battery be running before it
has discharge the same amount of charge as the battery in Q2? 4.A
car engine requires a battery that can produce a current of 40A to
start. A mechanic places a battery that can discharge 100C in 30s
into a car. Will this battery be good enough to start the car? Why?
5.For the question above, how much charge would the battery have to
discharge in 30s to start the engine? LO: Understand how to create
electrical circuits
Slide 156
Calculating voltage V = W/Q LO: Understand how to create
electrical circuits V = Voltage (Volts, V) W = Work done (Joules,
J) Q = Charge (Coulombs, c)
Slide 157
Example question 1 A battery transfers 30J for every coulomb of
charge that passes through the battery. What is the potential
difference of the battery? LO: Understand how to create electrical
circuits
Slide 158
Example question 2 A battery has a voltage rating of 40V. How
much energy is transferred by the battery if 20C of charge pass
through the battery? LO: Understand how to create electrical
circuits
Slide 159
Task 1.What is the voltage of a battery if it transfers 40J of
energy for every 10C that pass through it? 2.A builder requires a
400V battery to power his pneumatic drill. He is told that a
battery transfers 1000J for every 3C of charge that pass through
it. Will this battery be good enough? Why? 3.How much energy would
the battery in the question above need to transfer for every 3C to
have a voltage of 400V? 4.Battery A has a rating of 300V. Battery B
has a rating of 500V. What is the difference in the amount of work
done by the two batteries if 20C of charge pass through both
batteries? LO: Understand how to create electrical circuits
Slide 160
Slide 161
Circuit symbols LO: Understand how to create electrical
circuits
Slide 162
Series circuits IN A SERIES CIRCUIT, EVERYTHING IS CONNECTED
END TO END. THERE IS NO PLACE FOR THE CURRENT TO SPLIT IN THE
CIRCUIT. Tips for constructing circuits: 1.Make sure your circuit
is complete 2.Make sure that ammeters are connected in series
3.Make sure that voltmeters are connected in parallel LO:
Understand how to create electrical circuits
Slide 163
Practical Series circuits Aim: To investigate current and
voltage in a series circuit Method: 1.Create a series circuit with
one bulb 2.Measure the current in the circuit and voltage across
the bulb 3.Add another the bulb in series and repeat the process
4.Add a third bulb in series and repeat the process 5.Make sure you
measure the current in between the bulbs as well! LO: Understand
how to create electrical circuits
Slide 164
Practical Series circuits Conclusions: 1)The current through
each component in a series circuit is the same 2)The potential
difference of the source is shared out between the components in a
series circuit LO: Understand how to create electrical
circuits
Slide 165
Parallel circuits IN A PARALLEL CIRCUIT, THERE ARE BRANCHES
THAT SEPERATE THE CIRCUIT INTO SMALLER CIRCUITS. THERE IS MORE THAN
ONE PATH FOR THE CURRENT TO TAKE. Tips for constructing circuits:
1.Make sure your circuit is complete 2.Make sure that ammeters are
connected in series 3.Make sure that voltmeters are connected in
parallel LO: Understand how to create electrical circuits
Slide 166
Practical Parallel circuits Aim: To investigate current and
voltage in a parallel circuit Method: 1.Create a parallel circuit
with one bulb 2.Measure the current in the circuit and voltage
across the bulb 3.Add another the bulb in parallel and repeat the
process 4.Add a third bulb in parallel and repeat the process
5.Make sure you measure the current in each branch and the current
in just after the battery LO: Understand how to create electrical
circuits
Slide 167
Practical Parallel circuits Conclusions: 1)The potential
difference across each component is the same in a parallel circuit
2)The total current in the circuit is the sum of the currents
through the individual components in the circuit LO: Understand how
to create electrical circuits
Slide 168
Practical Current-Voltage relationship1 Aim: To investigate the
current/voltage characteristic of a resistor Method: 1.Create a
series circuit with one resistor, a battery pack, an ammeter and a
voltmeter 2.Slowly increase the voltage of the power pack from 2V
to 10V and repeat the process 3.Measure the current in the circuit
and the voltage across the resistor LO: Understand how to create
electrical circuits
Slide 169
Practical Current-Voltage relationship1 Draw a line of best fit
graph for your results with potential difference on the x-axis and
the current on the y-axis. A line of best fit is NOT dot-to-dot!
Make a conclusion for the current and voltage through a resistor.
Use your results to back up your conclusion LO: Understand how to
create electrical circuits
Slide 170
Knowledge Check LO: explain how safety features on a car work
What I enjoyed/learnt in todays lesson
Slide 171
To understand the relationship between current and voltage ALL
State the relationship between current and voltage in a circuit
MOST Perform calculations to find resistance SOME Explain why
certain components will not follow Ohms law
Slide 172
Recap In the last lesson, we made a graph for the current and
voltage through a resistor. The graph that we produced looked like
the one to the right. What does that tell us? LO: Understand the
relationship-between current and voltage in a circuit
Slide 173
Ohms Law Ohms Law states that the current through a resistor is
proportional to the potential difference provided the temperature
is constant LO: Understand the relationship-between current and
voltage in a circuit
Slide 174
Ohms Law V = IR LO: Understand the relationship-between current
and voltage in a circuit V = Voltage (V) I = Current (A) R =
Resistance (Ohms, )
Slide 175
Ohms Law 1 Calculate the potential difference across a 4
resistor when the current through it is 10A. LO: Understand the
relationship-between current and voltage in a circuit
Slide 176
Ohms Law 2 The potential difference across a 30 is 20V. What is
the current through the resistor? LO: Understand the
relationship-between current and voltage in a circuit
Slide 177
Task Calculate: 1.The resistance of a bulb if the current is
0.5 A and the potential difference across the bulb is 2 V. 2.The
potential difference across a bulb if the resistance of the bulb is
3 and the current flowing is 2 A 3.The potential difference across
a resistor of 5 with a current of 1.5 A. 4.The total resistance of
a circuit if the potential difference across the cell is 12V and
the current is 3 A. 5.The current flowing in a circuit with a total
resistance of 5 and a potential difference across the cell of 6V.
LO: Understand the relationship-between current and voltage in a
circuit
Slide 178
Practical Current-Voltage relationship2 Aim: To investigate the
current/voltage characteristic of a filament light bulb Method:
1.Create a series circuit with one bulb, a battery pack, an ammeter
and a voltmeter 2.Slowly increase the voltage of the power pack
from 2V to 10V and repeat the process 3.Measure the current in the
circuit and the voltage across the bulb LO: Understand the
relationship-between current and voltage in a circuit
Slide 179
Practical Current-Voltage relationship2 Draw a line of best fit
graph for your results with potential difference on the x-axis and
the current on the y-axis. A line of best fit is NOT dot-to-dot!
Make a conclusion for the current and voltage through a bulb. Use
your results to back up your conclusion. Extension: Explain why
this graph is not the same as for the resistor. Why is it not
following Ohms law? LO: Understand the relationship-between current
and voltage in a circuit
Slide 180
Non-Ohmic Components1 An LED does not follow Ohms law and is
designed to only allow current to flow through in one direction LO:
Understand the relationship-between current and voltage in a
circuit
Slide 181
Non-Ohmic Components2 An LED does not follow Ohms law and will
only light up when current to flows through in the right direction.
If current tries to flow in the other direction it encounters a
MAHOOSIVE resistance! LO: Understand the relationship-between
current and voltage in a circuit
Slide 182
Non-Ohmic Components2 An LDR is a component whose resistance
decreases as the light intensity that falls on it increases Where
would this be useful? LO: Understand the relationship-between
current and voltage in a circuit
Slide 183
Non-Ohmic Components3 A thermistor is a component whose
resistance decreases when the temperature increases. Where would
this be useful? LO: Understand the relationship-between current and
voltage in a circuit
Slide 184
Plenary Write a rap/rhyme about all you have learnt in this
lesson. Try to include as many of the following words in your rap
as possible! Ohms Law Thermistor LED LDR Filament lightbulb LO:
define ionic bonding
Slide 185
KEYWORDS: AC, DC, Current, Voltage, Live, neutral, earth, fuse,
circuit breaker KEYWORDS: AC, DC, Current, Voltage, Live, neutral,
earth, fuse, circuit breaker Describe features of mains electricity
ALL State what features of mains electricity MOST Describe how to
wire a plug SOME Explain how fuses and circuit breakers work
Starter Make a brainstorm about everything you know about
electricity in the home
Slide 186
Starter LO: describe features of mains electricity MAINS
ELECTRICITY
Slide 187
AC vs DC If you turn on any battery powered device the
electricity will only ever flow in one direction. This is called
DIRECT CURRRENT (d.c.) as the electricity goes around in just one
direction. LO: describe features of mains electricity
Slide 188
AC vs DC However, the same isnt true for mains electricity.
Mains electricity uses ALTERNATING CURRENT (a.c.) which repeatedly
flows in one direction and then reverses its flow. The frequency is
how many times it changes direction in one second LO: describe
features of mains electricity
Slide 189
Key points 1.Mains electricity uses a.c. 2.Mains electricity is
at 230V 3.Mains electricity has a frequency of 50Hz. This means it
changes direction 50 times in one second LO: describe features of
mains electricity
Slide 190
Cables and Plugs Cables and wires are designed to allow people
to use them without risk of hurting themselves. Most appliances are
supplied with three-core cable. This means the cable is made up of
three separate wires. LO: describe features of mains
electricity
Slide 191
Components of a plug and cable 1)Live wire (brown) This carries
the current to the appliance. Touching this can be deadly!
2)Neutral wire (blue) This completes the circuit and is usually at
0V 3)Earth wire (green/yellow) This earths the appliance in case
one of the wires touches the casing 4)Fuse This stops the flow of
current if it gets too high LO: describe features of mains
electricity
Slide 192
Practical Wiring a plug Aim: To wire a plug Method: 1.Take
apart everything in the plug 2.Put everything back together using
your knowledge of plugs and wiring 3.Make sure the wires are
connected to the correct pins! LO: describe features of mains
electricity
Slide 193
Earthing Components are earthed to make sure you dont get an
electric shock if the live wire accidentally touches the casing.
The electricity will flow harmlessly through the earth wire instead
of through you when you touch the casing. However, appliances with
plastic cases (hairdryers etc.) dont have earth wires. Why is this?
LO: describe features of mains electricity
Slide 194
Earthing Plastic is an insulator, so there is no danger if the
live wire touches the casing. Therefore, these appliances are
supplied with two- core cables instead of three-core cables i.e.
they dont have earth wires because they dont need them LO: describe
features of mains electricity
Slide 195
10 8 6 4 2 0 10 Minutes Start Timer Describe what is meant by
a.c. and d.c. Describe how a plug should be wired, explaining what
the different coloured wires represent Explain why appliances with
plastic cases are not supplied with three- core cable
Slide 196
Fuses A fuse is a component that has a wire running through it
made of a different material/thickness than the rest of the
circuit. It is designed to stop current that is too high flowing
through it. LO: describe features of mains electricity
Slide 197
Fuses Fuses have a rating based on the amount of current they
will allow through. For example, a 13A fuse will allow a maximum of
13 amps of current to flow through. If MORE than this tries to flow
through, the wire heats up and melts, breaking the circuit and
protecting the appliance LO: describe features of mains
electricity
Slide 198
Circuit Breakers Circuit breakers are fitted in newer homes.
They measure the difference in current in the live and neutral
wires. If the difference is too great, an electromagnetic switch
opens (trips) which stops the flow of current. They work a lot
faster than fuses and can be reset easily LO: describe features of
mains electricity
Slide 199
Circuit Breakers Use the textbook spread to create a poster on
fuses and circuit breakers. Your poster to include details of how
they work and advantages and disadvantages of both LO: describe
features of mains electricity
Slide 200
Knowledge check Copy the true sentences and change the false
sentences to make them true: 1.The earth wire in a three-core cable
is usually brown 2.Appliances with metal casings are supplied with
three- core cables 3.Fuses stop current flowing through a circuit
by melting when the current flowing through them is above a certain
value 4.A circuit breaker works by monitoring the difference in
current between the live and earth wire 5.Mains electricity uses
direct current at 100Hz. LO: describe features of mains
electricity
Slide 201
QWC Practice Using as much detail as possible, explain how
fuses and circuit breakers work to protect people and appliances.
Which, in your opinion, is the better choice for installation into
a home and why? 5-6 marks criteria: Knowledge of accurate
information appropriately contextualised Detailed understanding,
supported by relevant evidence and examples Answer is coherent and
in an organised, logical sequence, containing a wide range of
appropriate or relevant specialist terms used accurately The answer
shows almost faultless spelling, punctuation and grammar. LO:
describe features of mains electricity
Slide 202
Calculating power LO: describe features of mains electricity P
= V x I P = Power (w) V = Voltage (V) I = Current (A)
Slide 203
Example 1 Calculate the power of a bulb if it is supplied with
a potential difference of 230V and the current flowing through it
is 0.4A LO: describe features of mains electricity
Slide 204
Example 2 A kettle has a power rating of 1000W. If it is
supplied with a potential difference of 230V, what is the current
flowing through it? LO: describe features of mains electricity
Slide 205
Example questions 1.A light bulb is connected to a 2V supply
and experiences a current of 6.4A. What is the power rating of the
bulb? 2.A kettle has a power rating of 1500w. What is the potential
difference that it must be supplied with to have a current flowing
through it of 30A? 3.A student attaches a 10V supply to a bulb with
a power rating of 100w. What is the current running through the
bulb? 4.The student now connect a 25w bulb to the same supply. What
is the difference between the current going through this bulb
compared to the 100w bulb? 5.Bulb A transfers 1000J in 10seconds.
Bulb B transfers 1500J in 3 seconds. Which bulb will have a higher
current running through it when connected to a 12V supply? LO:
describe features of mains electricity
Slide 206
Calculating energy E = V x Q LO: Understand how to create
electrical circuits E = Energy transferred (Joules, J) V = Voltage
(Volts, V) Q = Charge (Coulombs, c)
Slide 207
Example question 1 A battery transfers 30J for every coulomb of
charge that passes through the battery. What is the potential
difference of the battery? LO: Understand how to create electrical
circuits
Slide 208
Example question 2 A battery has a voltage rating of 40V. How
much energy is transferred by the battery if 20C of charge pass
through the battery? LO: Understand how to create electrical
circuits
Slide 209
Task 1.What is the voltage of a battery if it transfers 40J of
energy for every 10C that pass through it? 2.A builder requires a
400V battery to power his pneumatic drill. He is told that a
battery transfers 1000J for every 3C of charge that pass through
it. Will this battery be good enough? Why? 3.How much energy would
the battery in the question above need to transfer for every 3C to
have a voltage of 400V? 4.Battery A has a rating of 300V. Battery B
has a rating of 500V. What is the difference in the amount of work
done by the two batteries if 20C of charge pass through both
batteries? LO: Understand how to create electrical circuits
Slide 210
BINGO
Slide 211
KEYWORDS: protons, neutrons, electrons, Rutherford, ion, alpha,
beta gamma KEYWORDS: protons, neutrons, electrons, Rutherford, ion,
alpha, beta gamma Understand the nature of radioactive decay ALL
State the structure of an atom MOST Describe how the structure of
an atom was found SOME Describe the nature and penetration of
different kinds of radioactive decay Starter Draw a diagram to show
what the atom looks like, highlighting where you would find
protons, neutrons and electrons
Slide 212
What is an atom made up of? Protons Positively charged
particles found inside the nucleus Neutrons Neutral particles found
inside the nucleus Electrons Negatively charged particles that
orbit the nucleus LO: understand the nature of radioactive
decay
Slide 213
Protons, neutrons and electrons ParticleRelative chargeRelative
mass Proton+11 Neutron01 Electron1/2000 LO: understand the nature
of radioactive decay
Slide 214
Relative sizes LO: understand the nature of radioactive
decay
Slide 215
Atomic and Mass number Atomic number: This is the number of
protons inside the nucleus of an atom WARNING: Even though the
number of protons and electrons in a neutral atom are the same,
make sure you say the correct definitions if you are asked in an
exam! Mass number: This is the number of protons + neutrons in the
nucleus of an atom LO: understand the nature of radioactive
decay
Slide 216
Atomic and Mass number Atomic number: This is the number of
protons inside the nucleus of an atom Mass number: This is the
number of protons + neutrons in the nucleus of an atom LO:
understand the nature of radioactive decay
Slide 217
Example 1 Calculate the following quantities for the element
below (i)Atomic number (ii)Mass number (iii)Number of protons
(iv)Number of electrons (v)Number of neutrons LO: understand the
nature of radioactive decay
Slide 218
Example 2 Calculate the following quantities for the element
below (i)Atomic number (ii)Mass number (iii)Number of protons LO:
understand the nature of radioactive decay
Slide 219
Task Use your periodic table to find the following quantities
for: nitrogen, oxygen, iron, platinum, gold, lead, mercury,
potassium, calcium, phosphorus, argon, xenon (i)Atomic number
(ii)Mass number (iii)Number of protons (iv)Number of electrons
(v)Number of neutrons If the numbers are decimals, round them to
the nearest whole number LO: understand the nature of radioactive
decay
Slide 220
The Plum Pudding Model - 1897 LO: understand the nature of
radioactive decay
Slide 221
Enter Rutherford LO: understand the nature of radioactive decay
Read through the worksheet on the work of Ernest Rutherford.
Highlight the key pieces of information and think about what the
conclusions could be for each of the observations that he
made.
Slide 222
Enter Rutherford LO: understand the nature of radioactive decay
Ernest Rutherford fired alpha particles at gold foil. Alpha
particles have a positive charge and he expected them to go through
the particle, with a small amount of deviation from their path
Slide 223
Gold Foil Experiment - 1911 LO: understand the nature of
radioactive decay The results are very different! Most alpha
particles go straight through with no deviation! Some, however, are
diverted through very large angles! The physics community is
flummoxed by this finding!
Slide 224
Gold Foil Experiment - 1911 LO: understand the nature of
radioactive decay The results are very different! Most alpha
particles go straight through with no deviation! Some, however, are
diverted through very large angles! The physics community is
flummoxed by this finding!
Slide 225
Conclusions LO: understand the nature of radioactive decay Most
of the fast, highly charged alpha particles went whizzing straight
through undeflected. SUGGESTS THAT MOST OF THE ATOM IS EMPTY
SPACE!!
Slide 226
Conclusions LO: understand the nature of radioactive decay Some
of the alpha particles were deflected back through large angles. A
very small number of alpha particles were deflected backwards!
SUGGESTS THAT THERE IS A CONCENTRATED POSITIVE MASS SOMEWHERE IN
THE ATOM.
Slide 227
Conclusions LO: understand the nature of radioactive decay A
very small number of alpha particles were deflected backwards!
SUGGESTS THAT THE CONCENTRATED MASS IS MINISCULE COMPARED TO THE
SIZE OF THE REST OF THE ATOM, BUT CONTAINS MOST OF THE MASS
Slide 228
Types of Radiation LO: understand the nature of radioactive
decay There are three different kinds of radiation. Each one has a
unique nature and penetration NameCompositionChargePenetrationExtra
Info Alpha Beta Gamma
Slide 229
Types of Radiation LO: understand the nature of radioactive
decay There are three different kinds of radiation. Each one has a
unique nature and penetration Alpha radiation: This particle is
made up of two protons and two neutrons (i.e. a Helium nucleus). It
has a charge of +2 and moves slowly because of its large mass. It
can be stopped by a few cm of air or by a piece of paper
Slide 230
Types of Radiation LO: understand the nature of radioactive
decay There are three different kinds of radiation. Each one has a
unique nature and penetration Beta radiation: During beta
radiation, a neutron turns into a proton inside the nucleus and
gives off an electron, which is fired from the nucleus. The
electron is small and light and so moves very fast! Beta particles
can be stopped by a thin sheet of aluminium
Slide 231
Types of Radiation LO: understand the nature of radioactive
decay There are three different kinds of radiation. Each one has a
unique nature and penetration Gamma radiation: Gamma radiation
usually follows alpha or beta decay. It is NOT a particle like the
other two. It is a high energy EM wave that travels at the speed of
light (the fastest that anything can travel Joel). It can only be
stopped by a very thick piece of lead or concrete.
Slide 232
Homework LO: understand the nature of radioactive decay Use the
book spread to create a leaflet about the uses and dangers of
radioactive substances. Focus on the specific uses of alpha, beta
and gamma radiation and also their specific dangers.
Slide 233
5, 5, 1 Summarise todays topic in 5 sentences. Reduce to 5
words. Now to 1 word. LO: understand the nature of radioactive
decay
Slide 234
KEYWORDS: fusion, fission, isotope, Half life, decay, chain
reaction KEYWORDS: fusion, fission, isotope, Half life, decay,
chain reaction Understand the nature of nuclear fusion and fission
ALL State the definition of an isotope MOST Describe the processes
of fusion and fission SOME Explain the design of fusion reactors
Starter Draw a spider diagram showing what you know about alpha,
beta and gamma radiation
Slide 235
Isotopes LO: understand the nature of fusion and fission The
diagram below shows three isotopes of hydrogen. What is the same
and different for each isotope of hydrogen?
Slide 236
Isotopes LO: understand the nature of fusion and fission An
isotope of an element has the same number of protons and neutrons
as the original, but a different number of neutrons.
Slide 237
Radioactivity of a substance LO: understand the nature of
fusion and fission
Slide 238
Radioactivity of a substance LO: understand the nature of
fusion and fission As a radioactive substance decays, the number of
particles left in it will start to reduce. Therefore the
radioactivity of the substance will begin to decrease. It will
continue to decrease, until the radioactivity has reached
zero!
Slide 239
Half-life LO: understand the nature of fusion and fission The
half-life of a substance is the time it takes for HALF of the
particles in a sample to decay or for the radioactivity of a
substance to decrease by HALF.
Slide 240
Half-life LO: understand the nature of fusion and fission What
is the half life of this substance?
Slide 241
Practical Modelling decay LO: understand the nature of fusion
and fission Aim: To model the radioactive decay of a substance
Method: 1.Count the number of original dice in the sample 2.Roll
all the dice simultaneously 3.All the dice that come up odd are
said to have decayed 4.Repeat until you get a nice set of
results
Slide 242
Practical Modelling decay LO: understand the nature of fusion
and fission Use the results of the graph to draw a line of best fit
graph. Assume that each time we threw the dice, one day had passed.
Use your graph to calculate the half life of the substance.
Slide 243
Task LO: understand the nature of fusion and fission Answer the
questions on the worksheet on calculating half-life
Slide 244
KEYWORDS: fusion, fission, chain reaction, Generator, turbine,
hydrogen KEYWORDS: fusion, fission, chain reaction, Generator,
turbine, hydrogen Understand the nature of nuclear fusion and
fission ALL Describe the process of fission and fusion MOST Explain
how fission/fusion can be used to generate electricity SOME
Evaluate the advantages and disadvantages of fission/fusion Starter
Label the atom
Slide 245
Starter LO: understand the nature of fusion and fission Draw
the diagram of the atom below and add the following labels:
electron, neutron, proton, nucleus
Slide 246
Recap LO: understand the nature of fusion and fission Protons
and neutrons are in the centre of the atom called the nucleus. The
electrons orbit around the nucleus.
Slide 247
Recap LO: understand the nature of fusion and fission In each
atom, the number of protons will ALWAYS be the same as the number
of electrons. This makes sure that the overall charge is zero.
ParticleCharge Proton+1 Neutron0 Electron
Slide 248
Recap LO: understand the nature of fusion and fission
http://www.youtube.com/watch?v=hhbqIJZ8wCM
Slide 249
Recap LO: understand the nature of fusion and fission
Slide 250
Slide 251
Nuclear Fission LO: understand the nature of fusion and fission
Nuclear fission is a process that uses atoms to generate VAST
amounts of energy.
Slide 252
Uranium nucleus Neutron Nuclear Fission LO: understand the
nature of fusion and fission To begin with, we have a simple
Uranium nucleus. Uranium is used because it is already unstable. A
slow moving neutron is fired at the Uranium.
Slide 253
Uranium nucleus Neutron Nuclear Fission LO: understand the
nature of fusion and fission The neutron attaches itself to the
uranium and makes it even more unstable! Unstable nucleus
Slide 254
Uranium nucleus Neutron Nuclear Fission LO: understand the
nature of fusion and fission The unstable Uranium splits into two
smaller nuclei, releasing energy in the process Unstable nucleus 2
smaller nuclei (e.g. barium and krypton)
Slide 255
Uranium nucleus Neutron Nuclear Fission LO: understand the
nature of fusion and fission Along with the energy, some more
neutrons are also released! Unstable nucleus 2 smaller nuclei (e.g.
barium and krypton) More neutrons
Slide 256
Chain reactions LO: understand the nature of fusion and fission
More neutrons These fission reactions produce a lot of energy and
are used in nuclear generators. However, each fission reaction
produces more and more neutrons.
Slide 257
Chain reactions LO: understand the nature of fusion and fission
More neutrons Each of the neutrons can cause more fission
reactions, releasing more energy and more neutrons. The reaction
can soon become an uncontrollable chain reaction, and when that
happens
Slide 258
Slide 259
Task LO: understand the nature of fusion and fission Create a
poster that has the following: A simple diagram of an atom An
explanation of nuclear fission A diagram to show the process of
nuclear fission A description of what a chain reaction is and why
they are bad. Leave space on your poster to add more information
later.
Slide 260
Using fission LO: understand the nature of fusion and
fission
Slide 261
Advantages/disadvantages of fission LO: understand the nature
of fusion and fission
Slide 262
Advantages/disadvantages of fission LO: understand the nature
of fusion and fission
Slide 263
Advantages/disadvantages of fission LO: understand the nature
of fusion and fission
Slide 264
Advantages/disadvantages of fission LO: understand the nature
of fusion and fission AdvantagesDisadvantages
Slide 265
Task LO: understand the nature of fusion and fission Add the
following to your poster: The diagram of the nuclear reactor A
step-by-step explanation of how the reactor works A table
explaining what the advantages and disadvantages of fission are A
brief explanation on whether or not you think fission should be
used to generate electricity
Slide 266
True or False? LO: understand the nature of fusion and fission
Copy the true sentences and change the false sentences to make them
true 1)Nuclear fission uses fast-moving electrons 2)The most common
fuel used in a nuclear reactor is uranium 3)Nuclear fission
involves one nucleus splitting into smaller nuclei and releasing
energy in the process 4)An advantage of nuclear fission is that it
doesnt produce any harmful radioactive waste 5)A chain reaction
occurs when too many neutrons cause fission reactions and the
process can no longer be controlled
Slide 267
Debate LO: understand the nature of fusion and fission RECENT
DISASTERS SUCH AS THE ONE THAT HAPPENED AT THE FUKISHIMA PLANT HAS
SHOWN THAT NUCLEAR FISSION IS WAY TOO DANGEROUS TO PRODUCE ENERGY.
ALL NUCLEAR POWER PLANTS IN THE UK SHOULD IMMEDIATELY BE
DISMANTLED!
Nuclear fusion LO: understand the nature of fusion and fission
Although the names sound very similar, fission and fusion are VERY
DIFFERENT PROCESSES.
Slide 271
Uranium nucleus Neutron Nuclear Fission LO: understand the
nature of fusion and fission In fission, one nuclei is split into
smaller nuclei to release energy! Unstable nucleus 2 smaller nuclei
(e.g. barium and krypton) More neutrons
Slide 272
Nuclear fusion LO: understand the nature of fusion and fission
In nuclear fusion, two nuclei are fused together to release energy.
It is the opposite of nuclear fission.
Slide 273
Where does this happen? LO: understand the nature of fusion and
fission Contrary to popular belief, our sun is not a massive
fireball. It is actually a massive fusion reactor!
Slide 274
Where does this happen? LO: understand the nature of fusion and
fission The sun is made up of mainly hydrogen. The high temperature
on the sun allows the hydrogen to fuse together and make helium,
releasing massive amounts of energy in the process
Slide 275
Why dont we use fusion? LO: understand the nature of fusion and
fission Fusion seems like a great process! We only need hydrogen to
do it (which we can get from water) and make helium, which is not a
greenhouse gasso why are we not using it?
Slide 276
Task LO: understand the nature of fusion and fission Watch the
video on nuclear fusion and answer the following questions: 1)What
is the temperature at the centre of the sun? 2)How much hotter is
the JET reactor? 3)What process does the sun use to generate
energy? 4)What kind of conditions are required to recreate fusion
on earth? 5)Why must robotic arms be used to move things inside the
core? 6)Why is fusion safer than fission?
http://www.bbc.co.uk/learningzone/clips/nuclear-fusion/6019.html
http://www.youtube.com/watch?v=5JaMBc2OrtI
Slide 277
Fusion future LO: understand the nature of fusion and fission
Although fusion isnt economically viable right now, it will
(probably!) be one of the main ways we generate energy in the
future. Lots and lots of research is currently being done into it
currently.
Slide 278
BINGO
Slide 279
KEYWORDS: protostar, red giant, white dwarf, black dwarf,
supernova, neutron star, Black hole KEYWORDS: protostar, red giant,
white dwarf, black dwarf, supernova, neutron star, Black hole
Understand the lifecycle of a star ALL State the main stages of a
stars development MOST Describe each stage and explain the factors
that influence the development of a star SOME Explain how solar
systems such as ours came into existence Starter Write one question
about stars that you want to know the answer to by the end of the
lesson
Slide 280
Stars LO: understand the lifecycle of a star To start with, we
will be watching a few short videos about stars. The videos will
give you important information about the lifecycle of stars, which
we will cover in greater detail later in the lesson.
http://www.bbc.co.uk/learningzone/clips/how-do-stars-
form/9789.html
http://www.bbc.co.uk/learningzone/clips/the-death-of-
stars/12239.html
http://www.bbc.co.uk/learningzone/clips/why-are-black-holes-
invisible/12240.html
Slide 281
Task LO: understand the lifecycle of a star Around the room is
information about stars and their lifecycle. Go around the room and
write the sentences in the correct order in your books to create
the star lifecycle. Add a diagram to go with each stage.
Slide 282
Nebula LO: understand the lifecycle of a star All stars start
their lives as part of a nebula. Nebulae are large clouds of dust
and gas (mainly hydrogen).
Slide 283
Protostar LO: understand the lifecycle of a star Over millions
of years, gravity will cause the dust and gas in the nebula to come
together. As it does this, the temperature increases until hydrogen
can fuse. When this happens, a protostar is born. This is kind of
like a baby star.
Slide 284
Main sequence star LO: understand the lifecycle of a star The
main sequence star is the next stage after a protostar. Hydrogen
fusion is now in full flow and the star is much hotter and brighter
than the protostar.
Slide 285
Red Giant star LO: understand the lifecycle of a star When a
star runs out of hydrogen, it begins to fuse other, heavier
elements. This releases more energy, causing the star to expand. It
also gives off red light, giving it the name Red Giant.
Slide 286
White dwarf LO: understand the lifecycle of a star When the red
giant has run out of all fuel and can fuse nothing more, it will
lose its outer layers. This leaves just the core, which is still
extremely hot. It is so hot it glows white hot, giving the name to
this stage the white dwarf.
Slide 287
Black dwarf LO: understand the lifecycle of a star After a long
enough time, the white dwarf will cool down enough so that it stops
glowing white hot. It is now called a black dwarf.
Slide 288
Task LO: understand the lifecycle of a star The lifecycle that
you have just covered is for stars about the same mass as our
sunHeavier stars, however, lead a slightly different life
Slide 289
Red Super Giant star LO: understand the lifecycle of a star
Following the main sequence, the star begins to fuse together
heavier elements. However, as it has far more fuel, it expands to a
much larger size and gives off much more energy.
Slide 290
Supernova LO: understand the lifecycle of a star For very heavy
stars, once they have run out of fuel, the star begins to collapse
in on itself. It continues to collapse until it reaches a critical
point when it cant collapse any more. This causes a MASSIVE
shockwave!
Slide 291
Supernova LO: understand the lifecycle of a star The shockwave
is so large that the outer layers EXPLODE outwards! The explosion
only lasts seconds, but can release as much energy in those seconds
as the star has released up to that point! It can be as bright as
the light from 10billion stars.
Slide 292
Neutron star LO: understand the lifecycle of a star After a
supernova, only the stars core is left behind. During the
collapsing process, this core is turned into just neutrons. The
resulting neutron star is very very dense. One spoonful of a
neutron star would weigh more than the Earth!
Slide 293
Black hole LO: understand the lifecycle of a star In some very
very rare cases, the core of a star left over after a supernova
will continue to collapse. It will keep getting smaller and smaller
until the whole star has collapsed into an infinitely small
point.
Slide 294
Black hole LO: understand the lifecycle of a star This
singularity has an immense gravitational force. Its attraction is
so strong that not even light can escape from it. Hence the name
black hole.
Slide 295
Task LO: understand the lifecycle of a star Using the help
sheet, create a comic strip to show how stars much larger than our
sun evolve after turning into a red super giant.
Slide 296
10 8 6 4 2 0 10 Minutes Start Timer State the stages of a stars
lifecycle that is about the same size as our sun. Describe a
protostar and explain how it is different from a main sequence star
Describe a supernova and explain why some stars will go supernova
and others will not.
Slide 297
Pupil as Teacher Summarise the lesson and what we have learnt
about for 20vivos and a positive! LO: understand the lifecycle of a
star