Posted by **Chelsea** on Thursday, November 15, 2012 at 10:04am.

Mass 1 with a mass of 28.5 kg starts at rest at the top of a frictionless from a height of 17 meters. It then slides down the incline and moves over a horizontal frictionless surface and collides inelastically (head on) with mass 2 which is of unknown mass. After the collision, the total kinetic energy of both masses is 60% of the initial total kinetic energy of both masses before the collision. What is the amount of mass 2 in kg?