Meaning & use

Newton's third law

phrase·Academic

The physics principle stating that for every action force, there is an equal and opposite reaction force.

See it in a sentence

Newton's third law explains why a rocket is pushed forward as gas shoots out behind it.

The teacher used a skateboard demonstration to illustrate Newton's third law.

A note on using this word

One of Isaac Newton's three laws of motion; often summarized as "for every action, there is an equal and opposite reaction."

Words with a similar meaning

This term is best learned through its definition and examples.

Choose a synonym to suit the sentence. Meanings can overlap without being identical.

Make it your own

Write a sentence using “Newton's third law”, then compare your use with the examples above.

Your draft stays on this page and is not sent anywhere.