Consider a frictionless track as shown in Figure P6.48. A block of mass m1 = 4.30 kg is released from A. It makes a head on elastic collision at B with a block of mass m2 = 9.00 kg that is initially at rest. Calculate the maximum height to which m1 rises after the collision.

Answer 1

Do this in three steps. I would need to see your figure to provide numerical values. I assume m1 initially slides down some ramp a certain distance.
(1) Use conservation of energy to get the speed of m1 just before impact
(2) Apply cnservation of energy and momentum to the collision to get the final velocity of m1. Presumably it will recoil somewhat.
(3) From the recoil velocity, and conservation of energy, get the height m1 travels back up the track.