1. The problem statement, all variables and given/known data A ring of mass M hangs from a thread, and two beads of mass m slide on it without friction, as shown. The beads are released simultaneously from the top of the ring and slide down opposite sides. Show that the ring will start to rise if m > 3M/2, and find the angle at which this occurs. 2. Relevant equations 3. The attempt at a solution First of all, I don't understand the situation physically. How does the ring move up exactly? What is the force propelling it upward?