A cubic block of mass m and side length b is placed on a smooth floor. A smooth and rigid rod of length L and with negligible mass is leaning against the block. A sphere of mass M is attached to the upper end of the rod. The lower end of the rod is fixed at point−O, but the rod can rotate freely around the point within the vertical plane. Initially the angle between the rod and the floor is α while the system is at rest. After releasing, find the speed of the block when the angle between the rod and the floor is β