Physics Laws & Theorems
Basic

Newton's Third Law

For every action there is an equal and opposite reaction.

Formula

FAB=−FBAF_{AB} = -F_{BA}

Variables

F_{AB}Force A on B
F_{BA}Force B on A

Example

A rocket pushes exhaust gas down; the gas pushes the rocket up with equal force.

Did You Know?

Rockets work in the vacuum of space precisely because of this law — they push exhaust one way and fly the other.

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