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Newton's third law of motion

Newton's third law of motion

1 3.9
Every force causes an equal force in the opposite direction
  • noun
  • /ˈnjuːtənz θɜrd lɔː ʌv ˈmoʊʃən/
  • Specialized
translation icon : tercera ley de movimiento de Newton
  • When a swimmer pushes the water backward, they move forward due to Newton's third law of motion.

Examples

  • Can you explain Newton's third law of motion to me?

  • This experiment demonstrates Newton's third law of motion by showing that every action results in an equal and opposite reaction.

  • Children see Newton's third law of motion in action when they push against a wall and feel themselves move backwards.

  • Rockets work thanks to Newton's third law of motion, as the hot gases push backward and the rocket moves forward.

  • When you jump off a boat, Newton's third law of motion explains why the boat moves in the opposite direction.

  • Wow! Newton's third law of motion explains so much about how we move!

  • According to Newton's third law of motion, when you push against a wall, the wall pushes back with equal force.

Synonyms

Newton's third law
vsNewton's third law of motion
  • Specialized
1 4.1

When one object pushes another, the other object pushes back equally

is the extended formal phrase adding a technical term
third law of motion
vsNewton's third law of motion
  • Specialized
1 4.2

Every push on an object causes an equal push back in the opposite direction

is the more formal titled expression including a name
law of action and reaction
vsNewton's third law of motion
  • Specialized
1 4.1

Every push or pull makes an equal force in the opposite direction

is the formal scientific title rather than plain wording

Surface Forms

Morphology

Newton's + third + law + of + motion

The components ('Newton's', 'third', 'law', 'of', 'motion') transparently indicate this is the third named scientific law concerning motion, so a B1 learner would infer it is a physics principle about movement. However, the specific content — that every action has an equal and opposite reaction — is conceptual and not derivable from the constituent words alone, so full meaning requires prior exposure or domain knowledge.

Etymology

The law Newton's third law of motion is easy to picture: if you push a wall, the wall pushes you back and you may move the other way. So it means every 'action' has an equal and opposite 'reaction'.