No matter what the masses are, the relative velocity of the objects after the collision is equal in magnitude and opposite in direction to the...

No matter what the masses are, the relative velocity of the objects after the collision is equal in magnitude and opposite in direction to the relative velocity before the collision. Example: A 120-kg astronaut floating at rest in space outside space capsule throws a 0.50 kg hammer such that it moves with a speed of 10 m/s relative to the capsule. What happens to the astronaut?