1. FRICTION
L/O: To understand that friction is the force that occurs when two objects move over each other.

2. What is friction?
Friction is a force that acts when two objects rub together.
When the two objects appear to be smooth, there is less friction.
When the two objects are rough, there is a greater amount of friction.

3. Friction
Even though some objects look smooth, microscopically they’re very rough & jagged.
As they slide against each other they kind of grind and drag against each other.

4. Friction is good…
Without friction we wouldn’t be able to walk, sit in a chair or drive safely. Everything would keep sliding and falling over.
We need friction between our feet and the ground or we would not be able to stand up.
When you are riding a bike and press the brakes, friction slows your bike down.

5. Friction is bad…
If you want to push something heavy, friction makes it harder to move.
Friction produces heat. Causing heat to build up is not always a good thing, especially inside a car engine.
We try to reduce the amount of friction in a car engine by adding oil.

6. Measuring friction We use a Newton Meter to measure forces.
The unit of measurement is Newtons (N).
As friction is a force, we can measure friction using a Newton Meter.

7. Shoes Which pair of shoes produces the most friction? The trainers?
The high heels?
The trainers?
The slippers?

8. Shoes Which pair of shoes produces the least friction? The trainers?
The high heels?
The trainers?
The slippers?

9. How could we check?

10. Investigating Friction
Next session we will be conducting an experiment using a toy car. We will be investigating how far the toy car travels down a ramp on different surfaces.

11. Investigating Friction
How will this help us to understand friction?
How could we carry out our experiment?
What equipment might we use?
How could we ensure a fair test?
What variables could we change?
How could we measure our results?