1. The problem statement, all variables and given/known data A 6.0 kg cart moving at 6.0 m/s collides with a 2.0 kg cart moving at 2.0 m/s in the same direction on the same track. The collision is cushioned by a perfectly elastic bumper attached to one of the carts. What are the velocities of the carts after the collision? What was the maximum potential energy stored in the bumper during the collision. 2. Relevant equations 1/2m1v12 + 1/2m2v22 = 1/2m1v'12 + 1/2m2v'22 3. The attempt at a solution I tried using the conservation of momentum and kinetic energy equations found in my textbook, but the answer never turns out properly. (It shows the answer, but not the work, in my book.) I think it's because it isn't a head-on collision, they are both going the same way. Any help would be appreciated. Thanks.