Force Pair

Key Stage 4

Meaning

A force pair is the two forces that occur when two objects interact.

About Force Pairs

The two forces in a force pair may be referred to as an action force and a reaction force.

When an object "A" exerts a force on object "B" then object "B" will exert a force on object "A". These are a force pair which will be equal in magnitude and opposite in direction to one another.

Examples

This diagram shows a force pair. It does not matter which is labelled "Action Force" and which is labelled "Reaction Force"

This diagram shows the weight as the "Action Force" and the normal contact force as the "Reaction Force".	This diagram shows a rocket with a force pair where each force is equal in magnitude but opposite in direction.