1.28P Force and momentum change
Force equals the rate of change of momentum, so larger momentum changes or shorter times produce larger average forces during interactions.
- Syllabus
- 2024
- Objective
- 1.28
- Level
- —
Exam analysis
Chance of appearing31%of analysed past papers
Latest appearanceNovember 2025
Most common paperPaper2P
Typical marks2–3
Common command terms
- Calculate
- Evaluate
Scoring notes
- Common mistake
- Using milliseconds directly instead of converting them to seconds.
Recent exam appearances
November 2025Paper2P [] · TZ03(a)(iii)[ 3 ]1.28P Force and momentum change
May 2025Paper2PR [] · TZ05(b)(ii)[ 3 ]1.28P Force and momentum change
November 2024Paper2P [null] · TZ06(c)[ 2 ]1.28P Force and momentum change
Jan 2023Paper2PR [null] · TZ07(a)[ 3 ]1.28P Force and momentum change
Jan 2022Paper2PR [null] · TZ02(a)(i)[ 3 ]1.28P Force and momentum change
Practice this objective
Coverage 2020–2025 · Updated 16 Jul 2026
1.28P Force and momentum change
Use force = change in momentum ÷ time taken, F = Δp/t = (mv − mu)/t.
Concept essentials
- Average force equals change in momentum divided by time taken.
- Shorter contact time gives a larger force for the same momentum change.
- Change in momentum depends on both final and initial momentum.
- The force direction follows the direction of the momentum change.
- The relationship can be rearranged to find force, time or velocity.