Two identical objects in outer space have a head-on collision and stick together. If, before the collision, one had been moving at 2 m/s and the other at 1 m/s, their combined speed after the collision would be

Question

Quizplus · Accepted Answer

The total momentum before the collision is conserved. The combined mass moves at the average velocity of the two objects, which is (2 m/s + 1 m/s) / 2 = 1.5 m/s / 2 = 0.5 m/s.

Two Identical Objects in Outer Space Have a Head-On Collision