If you're seeing this message, it means we're having trouble loading external resources on our website.

If you're behind a web filter, please make sure that the domains *.kastatic.org and *.kasandbox.org are unblocked.

Main content

Action and reaction forces

Review your understanding of action and reaction forces in this free article aligned to NGSS standards.

Key points:

  • For every force, there is an equal and opposite reaction force.
  • Let’s think about an example: when you push on a box, the box pushes back on you. Your push on the box is the action force. The force from the box on you is the reaction force. The two forces have the same strength, but they act in opposite directions.
  • Every force has a reaction force. A force and its reaction are generated together and happen at the same time.

Want to join the conversation?