2. Name 3 things that forces can do to an object
Questions
Name 3 things that forces can do to an object
What is the difference between contact and non-contact forces?
Classify the list of forces we generated earlier as contact or non-contact

5. On your diagram, place the four arrows in the correct place around the car and match with the appropriate label
How would it change if the car was:
Accelerating
Slowing down
Stationary?

6. There are forces on us all the time
True or False…
Which of these ideas about forces are true and which are false?
There are forces on us all the time
I’m not moving so there are no forces on me
Wood will float and metal will sink
Anything with air in it will float
Magnetism is a contact force as magnets can touch each other

7. Use the newton meters to investigate the forces needed to:
Open a cupboard door
Lift up your pencil case
Lift a weight of 100 grams
Lift a weight of 200 grams
Write your results in your notes…what do you notice about the results for the last two measurements?

11. Astronauts can experience ‘weightlessness’
Astronauts can experience ‘weightlessness’. They still have the same mass, as they still have the same atoms that make up their bodies. But why have they no weight in space?

12. Person
Mass
Weight on Earth (G = 10)
Weight on Moon (G = 1.7)
Weight on Mars (G = 3.8)
Weight on Jupiter (G = 25.4)
Weight on Pluto (G = 0.6)
Mr Griffiths

16. Look at these images.
Do they show situations where friction is being increased or reduced?
How?
Why?

17. Starter
A man tries to push this chest of drawers across the carpet. He cannot get it to move.
Explain in terms of forces what is happening…ensure you use the words gravity, friction and force in your answer.

19. Questions:
1. What forces are present on planes when they fly/
2. Which designs work best?
3. Explain your answer to question 2 using ideas about forces
4. What did you need to keep the same in each experiment?
5. Did your changes improve the distance the planes flew? Why or why not?

20. Why is this car shaped like this?

24. Air Resistance - This question was asked in a test
What is air resistance?
3 people gave 3 different answers. Decide who was right and write their answer down
Sarah wrote: Air resistance is when air stops objects from moving
Michael wrote: Air resistance slows objects down. It is caused by air particles hitting moving objects
Dan wrote : Air resistance is when air helps cars to move

25. What is water resistance?
Water resistance is similar to air resistance but acts in water. It is caused by water particles hitting moving objects
Answer the question
What is water resistance?
With a similar answer to the correct answer to the last question

26. Streamlining
Objects that move through air or water can reduce drag by being streamlined. This means that they can cut through the air or water easily.
The train on the right is more streamlined than the one on the left, helping it to move faster through the air

27. Streamlining – answer these questions in full sentences
What does streamlining aim to reduce?
How does it do this?
3. Which of these objects is the most streamlined? Which one do you think can go the fastest?
Concorde Cargo plane

28. Which of these objects are streamlined and which aren’t?
Streamlining
Which of these objects are streamlined and which aren’t?
Man running
Jellyfish
Olympic cyclist
Dolphin

29. Drag helps objects to move faster
True or False – decide whether these statements are true or false – write down the true ones
Drag helps objects to move faster
Streamlining helps objects to move faster by minimising drag
2 forms of drag are air and water resistance
Streamlined objects don’t cut through air or water more easily

30. What is the normal or ‘contact’ force?
What two things does friction depend upon?
Why does it take more effort to push a car across a road than a bike?
Why can you pull an ice-skater across ice more easily than you can pull a person across grass?
In the diagrams below, indicate the direction of the normal contact force

31. Investigating how the size of the normal ‘contact’ force and the nature of the surface affect friction
Newton meter cable Plank with weights
You can:
Change the size of the weights on the plank. This increases or decreases the size of the normal contact force
Change the surface on the desk.
By pulling on the newton meter you have to overcome friction in order to make the plank move. The size of the force on the newton meter therefore reflects the size of the friction.
Plan:
In your groups, write a plan for the experiment. Make sure you:
a) Write a step-by-step plan of what you will do
b) Decide what weights you will use
c) Decide how many times each measurement will be repeated
d) Draw a table for your results
e) Say what you will keep the sale each time
f) Say what you will change each time
Remember…your plan needs to explain how you will investigate both the surface and the size of the normal ‘contact’ force

32. Results and Conclusions
How did increasing the size of the normal ‘contact’ force affect friction?
How do you know?
How did changing the surface affect friction?
Why do you think some surfaces have greater friction than others?
Draw a graph to represent your results
How do you think the experiment could have been improved?
Do you think your results are reliable (is there a lot of variation between results or are they similar for one weight or surface)
Can you draw a conclusion?
Is there a clear trend?
Are there any anomalous results?

33. Exploring Magnetism
After completing each mini-experiment, remember to record your results properly
Suspend a bar magnet in a piece of paper as I have shown you. Using another bar magnet, move it towards the suspended one.
What happens when two of the same poles come close?
What happens when two different poles come close?
Using a bar magnet, try to pick up some of the following materials. Record which ones are magnetic
Copper
Iron
Plastic
Paper
Wood
Take a bar magnet and the petri dish containing the iron filings
Move the iron magnet close to the iron filings in the dish
What do you see?
Why do you think the iron filings have to be kept in the dish?
Take a bar magnet and place it on top of the mini-compasses
Draw what you see
Why do you think this happens?
Take a compass and a bar magnet
Where does the compass point when away from the magnet?
What about when close?

37. Answer these questions in full sentences
Magnetism
Answer these questions in full sentences
Define the words attract and repel?
What is a permanent magnet?
3. Give an example of a permanent magnet?
4. What 3 materials are magnetic?
5. What is an electromagnet?
6. How is an electromagnet different from a permanent magnet?
7. How can you increase the strength of an electromagnet?

38. Which object is elastic and which isn’t? What might object 1 be?
Draw line graphs to represent the lengths of two objects as forces are applied and then removed over a 10 second period
Use a full piece of graph paper and do both line graphs on the same axes
Time (s)
Object 1 length (cm)
Object 2 length (cm) 12 7 1 15 9 2 18 11 3 21 13 4 24 5 27 17 6 16 8 10
Length
Time
Which object is elastic and which isn’t? What might object 1 be?