1. The problem statement, all variables and given/known data A mass "m1" moves along the x axis with velocity of magnitude v0 on a frictionless table. It strikes another mass m2 which is initially at rest. The mass m1 goes off along the y-axis. If half the original kinetic energy is lost in the collision, with what speed and at what angle does m2 leave the point of collision? 2. Relevant equations 1/2KE(initial) = KE(final) (1/2)Pix=Pfx (1/2)Piy=Pfy 3. The attempt at a solution Pix=vom1 Pfx=u2m2cosθ Piy=0 Pfy=u1m1 - u2m2sinθ I think these are the initial and final components of momentum, but I don't know how to find θ and u2 in terms of known variables.