Physics
Force and motion
Class 8
Beginner
About 15 min
Premium
What can a force do? Shape and motion
Give a rolling ball a push forwards, backwards or sideways, and see how a force can speed it up, slow it down, change its direction or change its shape.
Core concept
A force can change an object's speed, direction or shape
Topic: Force and motion
A force: A push or a pull. Forces can start, stop or turn things. All key words is a push or a pull. Forces can change how an object moves: they can start it moving, make it go faster, slow it down, stop it or change its direction. Forces can also change an object's shape, by squashing, stretching, bending or twisting it. Some objects, like a rubber ball, spring back to their old shape when the force is removed (they are elastic). Others, like clay, stay changed (they are plastic).
What you will learn
- Describe how a force can speed up, slow down, stop or turn a moving object.
- Show that a bigger force causes a bigger change.
- Tell elastic and plastic changes of shape apart.
Before you start
- Know that force is measured in newtons (N).
Materials
- A rubber ball, a ball of clay and a football
Equipment
- A smooth table or floor
- Force meter to give a measured push
Procedure
- Push the rolling rubber ball forwards and record what happens.
- Push it backwards, against its motion, and record it.
- Push it sideways and record its new direction.
- Push the clay ball and the rubber ball with 8 N and compare their shapes afterwards.
How this simulation is simplified
- Every ball rolls at 1 m/s before the push, and friction is ignored.
- Each push lasts 0.1 s.