1. The problem statement, all variables and given/known data A cube of mass m slides down a circular path of radius r cut into a larger block of mass M. M rests on a table, and friction is ignored. Both blocks start at rest and m starts at the top of the circular path. What is the velocity v of the the small cube as it leaves the larger cube? 2. Relevant equations U = mgr since the radius of the circular path is the same as the height the smaller cube starts K = 1/2mv^2 pm = pM (momentum) 3. The attempt at a solution At first glance, I just set U = K, and solved for v, but I realized the v the small cube leaves will affect the larger cube's momentum. The problem is I can't figure out how to setup the momentum portion of the problem.