Physics · GCSE · Forces & Motion

Conservation of momentum

Conservation of momentumFree9:03Heddy Score 3 of 7, below the standard

What you need to know

  • Total momentum is conserved in a system with no resultant external force.
  • Calculate each object’s momentum from its mass and velocity, then add the momenta with consistent signs.
  • Equate the total before a collision with the total afterwards to find an unknown velocity.

In this clip

Runs 9:03, from 0:00 to 9:03 of the full video.

Heddy Score3/7, Below the standard
See the seven stars
  • Trusted source · passed. The creator's own upload, live and playable here.
  • On the map · not judged yet. A teacher watched it: it mainly teaches this map topic.
  • Spec-true · not judged yet. Accurate, and right for the current UK specification.
  • Focused · passed. One idea, short enough to watch in one go.
  • Accessible · passed. Good captions, clear sound and pictures.
  • Safe for children · not judged yet. Right for 11 to 16 year olds, with no sales pitch.
  • Proven · not judged yet. Earned from our students: they learn from it, find it helpful and watch it to the end.
★ passed · ☆ pending · ✕ failed
Our students

Not enough students yet

Our own students' answers. These are what move ★7 Proven.
On YouTube

390K views · 3.97K likes · GPB Education 83.3K subscribers

As reported by YouTube on 2026-11-02. Not part of the Heddy Score.
How the Heddy Score works

Why we picked it

The billiard and skating examples connect momentum conservation with calculations.

GPB Education on YouTubechecked 2026-10-18

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