What a force can do
Start, speed up, turn or reshape.
Four situations
A box is at rest. A ball is rolling. A ball is hit from the side. A rubber band is stretched.
What could a force do to these objects?
What this lesson covers
The idea
A force applied on an object may make it move from rest, change its speed, change its direction of motion, change its shape, or cause several of these; none of these changes happens without a force.
Four situations
A box is at rest. A ball is rolling. A ball is hit from the side. A rubber band is stretched.
What could a force do to these objects?
- Change what they are doing, or their shape
- Nothing at all
- Make them vanish
Apply a force
Choose a scene, then press Apply a force. Do it for all four scenes.
Four effects
The box started to move. The ball changed its speed. The other ball changed direction. The rubber band changed shape. None of these happens without a force.
A force may make an object move from rest, change its speed, change its direction of motion, change its shape, or cause several of these. None of them happens without a force.
- Object | What the force does
- Box at rest | Makes it move
- Rolling ball | Changes its speed
- Ball hit from the side | Changes its direction
- Rubber band | Changes its shape
Notes
A force may make an object move from rest, change its speed, change its direction, or change its shape. None of these happens without a force.
Check yourself
A fielder stops a moving ball. The force changes the ball's …
Turning the steering handle of an autorickshaw changes its …
Rolling a chapati with a rolling pin changes the chapati's …
The speed of an object changes. What must have acted on it?
- shape. Stopping the ball changes its speed, not its shape.
- colour. A force does not change colour. Here it changes the speed.
- speed — correct. Yes!
- direction of motion — correct. Yes!
- speed only. Turning changes the direction of motion.
- colour. A force does not change colour.
- direction of motion. The chapati's shape changes when you roll it.
- shape — correct. Yes!
- speed. The chapati's shape changes when you roll it.
- Nothing, speed changes by itself. None of these changes takes place without a force.
- Only its colour. A change in speed needs a force.
- A force — correct. Yes!