1.29P Newton’s third law
Newton’s third law states that interacting objects exert equal-magnitude forces on each other in opposite directions during the same interaction.
- Syllabus
- 2024
- Objective
- 1.29
- Level
- —
Exam analysis
Chance of appearing23%of analysed past papers
Latest appearanceNovember 2025
Most common paperPaper2PR
Typical marks1–2
Common command terms
- Draw
- State
- Identify
- Describe
Scoring notes
- Common mistake
- Giving the opposite force in the same direction as the original force.
Recent exam appearances
November 2025Paper2P [] · TZ01(b)(iv)[ 1 ]1.29P Newton’s third law
November 2025Paper2P [] · TZ01(b)(i)[ 1 ]1.29P Newton’s third law
May 2024Paper2PR [null] · TZ05(a)[ 2 ]1.29P Newton’s third law
Jan 2023Paper2PR [null] · TZ07(b)[ 2 ]1.29P Newton’s third law
Jan 2022Paper2PR [null] · TZ02(a)(ii)[ 1 ]1.29P Newton’s third law
Practice this objective
Coverage 2019–2025 · Updated 16 Jul 2026
1.29P Newton’s third law
Demonstrate an understanding of Newton’s third law
Concept essentials
- Third-law force pairs have equal magnitude.
- The two forces in a third-law pair act in opposite directions.
- Each force in the pair acts on a different object.
- Collision forces between two objects are equal in size even when their motion changes differently.
- A third-law arrow should be drawn on the other object and in the opposite direction.