Newton realized that
forces always come in pairs. These pairs of forces are equal
to each other in sizebut opposite
in direction. He called the forces "action and reaction".
(one direction) = Reaction (opposite direction)
Here are some more examples.
Check your understanding:
Identify the action-reaction
pair of forces.
1. A book resting on a table.
2. A person swimming.
Follow the links to learn more about
Newton's Third Law of Motion.
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