Physics (AS & A Level) · May / June 2016 · Paper 11 · Question 10

Two spheres approach each other along the same straight line. Their speeds are u1 and u2 before they collide. After the collision, the spheres separate with speeds v1 and v2 in the directions shown below. The collision is perfectly elastic. Which equation must be correct?

1. Au1 – u2 = v2 + v1
2. Bu1 – u2 = v2 – v1
3. Cu1 + u2 = v2 + v1
4. Du1 + u2 = v2 – v1

As printed in the paper