Physics (AS & A Level) · May / June 2023 · Paper 13 · Question 10

A perfectly elastic collision occurs between two objects X and Y. The mass of X is m and the mass of Y is 4m. Object X travels at speed v before the collision and speed \frac{3v}{5} in the opposite direction after the collision. Object Y is stationary before the collision. What is the kinetic energy of Y after the collision?

1. A\frac{8}{10} mv^2
2. B\frac{34}{50} mv^2
3. C\frac{16}{50} mv^2
4. D\frac{1}{5} mv^2

As printed in the paper