1. The problem statement, all variables and given/known data The drawing below shows two laboratory carts (each has a mass of 1.0 kg) X and Y in contact with a compressed exploder spring between them. The mass on cart Y is 2.17 kg, distance A is 60 cm, distance B is 90 cm. What mass must be placed on cart X, such that after the explosion both carts will hit the ends of the track at the same time? After the explosion has taken place, which of the following statements regarding the kinetic energies, EK, and the magnitudes of the momenta, pi, are correct or incorrect? (Note: The subscripts x and y refer to the carts, not the direction along x or y.) px < py Ey = 2/3 Ex Ex < Ey py = px/2 px = py 2. Relevant equations p = mv F(delta t)= mvf - mv0 3. The attempt at a solution What I wanted to do was find the momentum for each of these and then somehow find the time it would take the carts as they are to get to their respective ends, but with no velocities given I'm at a total loss. How should approach this problem? As for the second half, I pretty much suck at true/false type stuff I already guessed at incorrectly 3 times so I'd rather save my remaining 4 guesses. Anyone willing to help me out?