MOMENTUM

1 mark · Easy

State the law of conservation of momentum.

Work this out on paper, then compare with the answer and worked solution below. With a free account you can submit written answers for marking.

Show answer

The total momentum before and after a collision is the same provided no external forces act.

Also accept: Momentum is conserved in a closed system.; Total momentum remains constant if no external force acts.

Common mistakes: Not mentioning no external forces; Describing energy instead of momentum

Show mark scheme and worked solution

Marking points

B1 · 1 mark · Correct statement of conservation of momentum including reference to no external forces.

Worked solution

The total momentum of objects before a collision is equal to the total momentum after the collision, provided there are no external forces.