Physics (AS & A Level) · Oct / Nov 2021 · Paper 13 · Question 10

The diagram shows two spheres approaching each other head-on. Each sphere has speed u. One sphere has mass 2m and the other has mass m. Which diagram shows the result of a perfectly elastic collision?

1. A2m moves left at u/3, m moves right at 5u/3
2. B2m moves left at u/6, m moves right at 2u/3
3. C2m moves right at u/6, m moves right at 2u/3
4. Dthe spheres stick together, moving right at u/3

As printed in the paper