ForcesKey Facts

Newton's Third Law — Action-Reaction

Part of Newton's Laws of Motion · GCSE GCSE Physics revision

This key facts covers Newton's Third Law — Action-Reaction within Newton's Laws of Motion for GCSE Physics. Revise Newton's Laws of Motion in Forces for GCSE Physics with 24 exam-style questions and 15 flashcards. This topic shows up very often in GCSE exams, so students should be able to explain it clearly, not just recognise the term. It is section 6 of 15 in this topic. Use this key facts to connect the idea to the wider topic before moving on to questions and flashcards.

Topic position

Section 6 of 15

Practice

24 questions

Recall

15 flashcards

📜 Newton's Third Law — Action-Reaction

Statement: When object A exerts a force on object B, object B exerts an equal and opposite force on object A.

Key features of Third Law pairs:

  • Equal in magnitude
  • Opposite in direction
  • Act on DIFFERENT objects
  • Same type of force
  • Act simultaneously

Examples:

  • You push wall → wall pushes you (contact forces)
  • Earth pulls you → you pull Earth (gravitational)
  • Rocket pushes gas down → gas pushes rocket up
  • Swimmer pushes water back → water pushes swimmer forward

Keep building this topic

Read this section alongside the surrounding pages in Newton's Laws of Motion. That gives you the full topic sequence instead of a single isolated revision point.

Practice Questions for Newton's Laws of Motion

According to Newton's First Law, what happens to an object when there is no resultant force acting on it?

  • A. It accelerates in the direction of motion
  • B. It remains at rest or continues moving at constant velocity
  • C. It decelerates and eventually stops
  • D. It changes direction
1 markfoundation

A spaceship is travelling through deep space far from any planets. The engines are switched off. Explain what will happen to the motion of the spaceship and why.

2 marksstandard

Quick Recall Flashcards

Key Concepts
Unit: Newton metres (Nm)
Key Concepts
A moment is the turning effect of a force

24 questions on Newton's Laws of Motion — practise free

Instant marking, adaptive difficulty, and 15 spaced repetition flashcards. Free until your GCSEs.

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