Forces are either pushes or pulls.

• Hitting a ball is an example of a push force. Towing a car is an example of a pull force.

Forces can have different effects:

• Speed up an object

• Slow down an object

• Change the direction of motion

• Squash or stretch an object

• If the object causing the force needs to touch the object it acts on then the force is called a contact force.

E.g. A hockey stick striking a ball.

• Non-contact forces are the forces which act over a distance without requiring contact between the object creating the force and object it acts on.

E.g. A magnet attracting a paper-clip.

• A non-contact force creates a force field- an area in which the force has an effect. The strength of the force field decreases with distance away from the source of the force.