1. Cars
And Forces - Pressure

2. Pressure Starter – What is pressure? To be able to: All Most Some
If forces balance, do they cancel each other out?
To be able to:
All
Most
Some
Say what is meant by pressure
(MYP 2/3)
Calculate pressure
(MYP 3/4)
Explain how forces can be spread out or concentrated on a small area
(MYP 5/6)
Levels of Learning At which students are required to demonstrate their ability Associated action verbs
Knowledge
to recall a wide range of knowledge, facts and experiencesdescribe, recall, define, state, recognise, name, list, underline, reproduce, measure, write, label, identify, acquire
Comprehension
to grasp the meaning of their acquired knowledge, and to process, translate and interpret this knowledgecomprehend, understand, draw, interpolate, extrapolate, predict, to have insight into, translate, illustrate
Application
to apply knowledge and comprehension in different situations, relate material, and infer from factsapply, show, demonstrate, perform, use, relate, develop, transfer, infer, construct, explain
Analysis
to analyse data or material, breaking it down into its component parts so that its organisational structure may be understoodanalyse, identify, separate, detect, break down, discriminate, categorise, distinguish
Synthesis
to synthesise and combine elements to produce a coherent whole and make logical deductionscombine, restate, summarise, précis, generalise, conclude, derive, organise, design, deduce, classify, formulate, propose
Evaluation
to evaluate data, make judgements and assess materialevaluate, judge, decide, choose, assess, contrast, criticise,select, defend support, attack, seek out, compare, determine.
Starter – What is pressure?

3. Pressure is exerted whenever a force is applied over an area.
What is pressure?
Pressure is exerted whenever a force is applied over an area. 1. 2.
If the same force is applied in each picture, which arm exerts the highest pressure on the board?

4. High and Low Pressure 1. 2.
The arm applies a force to the board via a fingertip.
The force acts over a
small area and so
produces a high pressure.
The same force is now acting over a larger area – the palm has a greater surface area
than the fingertip. A lower pressure is produced.

5. Pressure Pressure depends on ______ and ______
Explain how the following work:
A sharp knife is easier to use then a blunt knife.
A drawing pin.
A woman with stilettos on might damage a floor more than an elephant would.
Pressure depends on ______ and ______

6. Pressure Pressure depends on two things:
How much force is applied, and
How big (or small) the area on which this force is applied.

7. Calculating pressure f p x a force pressure = area
Pressure is the force per unit area
and is calculated using this formula:
p x a f
pressure =
area
force
Pressure is measured in: newtons per square metre (N/m2),
Pressure can also be measured in: newtons per square millimetre (N/mm2); newtons per square centimetre (N/cm2).

8. Pressure calculations
Mr Bobdy Bilda has a block
1. What is the pressure of Bobdy’s block on the ground?
The force is the weight = 60N
Area on the ground = 2m x 1m
= 2m2
So the pressure of the block is /2 = 30N/m2
What if Bobdy turned the block on its side?
Weight 60N 3m 1m 2m

9. Pressure Questions 1000 N/m2 0.5 N/cm2 5 cm 15,000 N
Calculate the pressure exerted by a 1000N elephant when standing on the floor if his feet have a total area of 1m2.
A brick is rested on a surface. The brick has an area of 20cm2. Its weight is 10N. Calculate the pressure.
A woman exerts a pressure of 100N/cm2 when standing on the floor. If her weight is 500N what is the area of the floor she is standing on?
The area of contact of four car tyres with the road is 300 cm2. The pressure exerted is 50 N/cm2. Work out the weight of the car.
1000 N/m2
0.5 N/cm2
5 cm
15,000 N

10. How do skates work?

13. Plenary
Prepare a short live presentation to explain to Year 3 children how skates and skis work.

14. Homework
Update the mind map you made earlier. Add topics and keywords that we have used recently. Stick it in your book

15. Pressure To be able to: All Most Some Say what is meant by pressure
If forces balance, do they cancel each other out?
To be able to:
All
Most
Some
Say what is meant by pressure
(MYP 2/3)
Calculate pressure
(MYP 3/4)
Explain how forces can be spread out or concentrated on a small area
(MYP 5/6)
Levels of Learning At which students are required to demonstrate their ability Associated action verbs
Knowledge
to recall a wide range of knowledge, facts and experiencesdescribe, recall, define, state, recognise, name, list, underline, reproduce, measure, write, label, identify, acquire
Comprehension
to grasp the meaning of their acquired knowledge, and to process, translate and interpret this knowledgecomprehend, understand, draw, interpolate, extrapolate, predict, to have insight into, translate, illustrate
Application
to apply knowledge and comprehension in different situations, relate material, and infer from factsapply, show, demonstrate, perform, use, relate, develop, transfer, infer, construct, explain
Analysis
to analyse data or material, breaking it down into its component parts so that its organisational structure may be understoodanalyse, identify, separate, detect, break down, discriminate, categorise, distinguish
Synthesis
to synthesise and combine elements to produce a coherent whole and make logical deductionscombine, restate, summarise, précis, generalise, conclude, derive, organise, design, deduce, classify, formulate, propose
Evaluation
to evaluate data, make judgements and assess materialevaluate, judge, decide, choose, assess, contrast, criticise,select, defend support, attack, seek out, compare, determine.
In a short sentence, explain how FORCE and PRESSURE are:
Similar
Different

16. Is a drawing pin well designed?
Pressure - revisited
Is a drawing pin well designed?
To be able to:
All
Most
Some
State how to calculate pressure
(Level 4)
Calculate pressure in different situations
(Level 5)
Design an experiment to calculate large and small pressures
(Level 7)
Levels of Learning At which students are required to demonstrate their ability Associated action verbs
Knowledge
to recall a wide range of knowledge, facts and experiencesdescribe, recall, define, state, recognise, name, list, underline, reproduce, measure, write, label, identify, acquire
Comprehension
to grasp the meaning of their acquired knowledge, and to process, translate and interpret this knowledgecomprehend, understand, draw, interpolate, extrapolate, predict, to have insight into, translate, illustrate
Application
to apply knowledge and comprehension in different situations, relate material, and infer from factsapply, show, demonstrate, perform, use, relate, develop, transfer, infer, construct, explain
Analysis
to analyse data or material, breaking it down into its component parts so that its organisational structure may be understoodanalyse, identify, separate, detect, break down, discriminate, categorise, distinguish
Synthesis
to synthesise and combine elements to produce a coherent whole and make logical deductionscombine, restate, summarise, précis, generalise, conclude, derive, organise, design, deduce, classify, formulate, propose
Evaluation
to evaluate data, make judgements and assess materialevaluate, judge, decide, choose, assess, contrast, criticise,select, defend support, attack, seek out, compare, determine.
Starter – what are the important ideas about Pressure Agree on your table ... Ask others if you need to

17. Under Pressure
Why would a lady in high heels standing on your foot hurt more than an elephant standing on your foot?
medium pressure
high pressure

18. Possible Demonstration
Demonstrate air pressure with 30cm ruler
Balance over end of desk and strike overhang with, successively
Sheet of newspaper screwed up tightly.
Sheet of newspaper carefully folded into 8.
Sheet of newspaper spread out carefully.
What causes what you see.
Safety: watch where you are propelling the ruler and missile

19. Pressure in Liquids and Gases
low pressure
Pressure in a liquid acts in all directions and increases with depth.
high pressure
Gases
The particles move in all directions and push on their container (“pneumatic”)

20. Practical Work in groups of 4
What is the greatest pressure you can put on the floor of the room?
... And the smallest
Equipment: Newton scales, graph paper, mural paper
You should be prepared to estimate!

21. Is a drawing pin well designed?
Pressure - revisited
Is a drawing pin well designed?
Review
To be able to:
All
Most
Some
State how to calculate pressure
(MYP 1/2)
Calculate pressure in different situations
(MYP 3/4)
Design an experiment to calculate large and small pressures
(MYP 5/6))
Levels of Learning At which students are required to demonstrate their ability Associated action verbs
Knowledge
to recall a wide range of knowledge, facts and experiencesdescribe, recall, define, state, recognise, name, list, underline, reproduce, measure, write, label, identify, acquire
Comprehension
to grasp the meaning of their acquired knowledge, and to process, translate and interpret this knowledgecomprehend, understand, draw, interpolate, extrapolate, predict, to have insight into, translate, illustrate
Application
to apply knowledge and comprehension in different situations, relate material, and infer from factsapply, show, demonstrate, perform, use, relate, develop, transfer, infer, construct, explain
Analysis
to analyse data or material, breaking it down into its component parts so that its organisational structure may be understoodanalyse, identify, separate, detect, break down, discriminate, categorise, distinguish
Synthesis
to synthesise and combine elements to produce a coherent whole and make logical deductionscombine, restate, summarise, précis, generalise, conclude, derive, organise, design, deduce, classify, formulate, propose
Evaluation
to evaluate data, make judgements and assess materialevaluate, judge, decide, choose, assess, contrast, criticise,select, defend support, attack, seek out, compare, determine.
Starter – what are the important ideas about Pressure Agree on your table ... Ask others if you need to

22. How does depth affect water pressure?
Look at the graph below showing the changes in water pressure with depth:

23. As the depth increases the water pressure increases.
a) Describe the pattern shown in the graph.
As the depth increases the water pressure increases.

24. The inflated balloon would decrease in size the deeper it went.
b) Predict what would happen to the size of an inflated balloon if it was carried down beneath the surface of the water by a diver.
The inflated balloon would decrease in size the deeper it went.

25. c) Explain your reasons for your prediction in part ‘b’.
The increasing water pressure would exert a force on the sides of the balloon, compressing the gas contained inside.

26. Plenary: Pressure – highest to lowest
The woman weighs 400N Each stiletto heel has an area of 1cm2
The elephant weighs 4000N. Each foot has an area of 100cm2

27. Do we live under a sea of air?
Atmospheric Pressure
Do we live under a sea of air?
To be able to:
All
Most
Some
Describe how the atmosphere pushes down on us
(MYP 1/2)
Explain how atmospheric pressure makes some things happen
(MYP 3/4)
Explain atmospheric pressure using particle theory
(MYP 5/6)
Levels of Learning At which students are required to demonstrate their ability Associated action verbs
Knowledge
to recall a wide range of knowledge, facts and experiencesdescribe, recall, define, state, recognise, name, list, underline, reproduce, measure, write, label, identify, acquire
Comprehension
to grasp the meaning of their acquired knowledge, and to process, translate and interpret this knowledgecomprehend, understand, draw, interpolate, extrapolate, predict, to have insight into, translate, illustrate
Application
to apply knowledge and comprehension in different situations, relate material, and infer from factsapply, show, demonstrate, perform, use, relate, develop, transfer, infer, construct, explain
Analysis
to analyse data or material, breaking it down into its component parts so that its organisational structure may be understoodanalyse, identify, separate, detect, break down, discriminate, categorise, distinguish
Synthesis
to synthesise and combine elements to produce a coherent whole and make logical deductionscombine, restate, summarise, précis, generalise, conclude, derive, organise, design, deduce, classify, formulate, propose
Evaluation
to evaluate data, make judgements and assess materialevaluate, judge, decide, choose, assess, contrast, criticise,select, defend support, attack, seek out, compare, determine.
Starter – An egg has a diameter of 4cm. How could you get it into a flask with an opening 3.5 cm wide?

28. Egg in a bottle demonstration
Show a wide mouthed conical flask and an egg
Challenge one of the pupils to try and push the egg into the flask intact – it will get messy!
Put a little water in the flask and place a hard boiled shelled egg on the mouth. Heat the water using a Bunsen, switch off when the water is boiling and the egg starts to wobble. The egg should slowly be sucked in intact.
What is happening?
Discuss the pressure of the atmosphere and why we don’t feel it.
(video on next slide in case it doesn’t work!)

29. Air Pressure How did the egg get into the bottle?
Why does the plastic bottle collapse?
Why does a helium balloon float? (After all it weighs something!)

30. Numbered heads together
Listen to the question and the time you have to solve it
Teacher then says “Butts up”.
Stand up and lean into the centre of the table to decide on the answer.
When you all know the answer, sit down.
The teacher picks a number.
That pupil from each team writes the answer on a whiteboard and stands up. This must be done in silence.
The teacher gives a signal and each team shows the answer at the same time.

31. Pressure Challenge 1. Why did the egg go into the bottle?
Diagram and 5 key words
1. Why did the egg go into the bottle?
2. Why did the bottle collapse?
3. Why do you feel pressure on your eardrums in the deep end of the pool?
 4. Why does water boil at around 70ºC up Mount Everest?
 5. Why can divers only go so far without a submersible?

32. Atmospheric Pressure
Do we live under a sea of air?
To be able to:
All
Most
Some
Describe how the atmosphere pushes down on us
(MYP 1/2)
Explain how atmospheric pressure makes some things happen
(MYP 3/4)
Explain atmospheric pressure using particle theory
(MYP 5/6)
Levels of Learning At which students are required to demonstrate their ability Associated action verbs
Knowledge
to recall a wide range of knowledge, facts and experiencesdescribe, recall, define, state, recognise, name, list, underline, reproduce, measure, write, label, identify, acquire
Comprehension
to grasp the meaning of their acquired knowledge, and to process, translate and interpret this knowledgecomprehend, understand, draw, interpolate, extrapolate, predict, to have insight into, translate, illustrate
Application
to apply knowledge and comprehension in different situations, relate material, and infer from factsapply, show, demonstrate, perform, use, relate, develop, transfer, infer, construct, explain
Analysis
to analyse data or material, breaking it down into its component parts so that its organisational structure may be understoodanalyse, identify, separate, detect, break down, discriminate, categorise, distinguish
Synthesis
to synthesise and combine elements to produce a coherent whole and make logical deductionscombine, restate, summarise, précis, generalise, conclude, derive, organise, design, deduce, classify, formulate, propose
Evaluation
to evaluate data, make judgements and assess materialevaluate, judge, decide, choose, assess, contrast, criticise,select, defend support, attack, seek out, compare, determine.
Starter – An egg has a diameter of 4cm. How could you get it into a flask with an opening 3.5 cm wide?

33. Draw a concept map linking at least the following words and units
Plenary
Draw a concept map linking at least the following words and units
Counter balance
Force
Moment N
Weight
Pivot
N/cm2 Kg
Pressure
Turning effect
Hydraulic
Balance
N/m2
Friction Nm
Pneumatic
Lever
Atmospheric

34. Get another picture of your car… Draw accurate force diagrams on it…
Homework
Get another picture of your car…
Draw accurate force diagrams on it…
Now research how your car is designed to use or overcome the forces acting upon it!