Inelastic collisions in one dimension: Two objects of the same mass move along the same line in opposite directions. The first mass is moving with speed v. The objects collide, stick together, and move with speed 0.100v in the direction of the velocity of the first mass before the collision. What was the speed of the second mass before the collision?

Question

Quizplus · Accepted Answer

In an inelastic collision, momentum is conserved. Let m be the mass of each object. The initial momentum is m*v - m*u, where u is the speed of the second mass. After collision, the combined mass 2m moves with speed 0.100v, so the final momentum is 2m*0.100v. Setting initial and final momentum equal: m*v - m*u = 2m*0.100v. Solving for u gives u = 0.800v.

Inelastic Collisions in One Dimension: Two Objects of the Same