Two blocks are connected with a light string that is hung over a pulley, as shown in the diagram to the right. One block has twice the mass of the other, and the pulley
has the same mass as the heavier block. The pulley consists of a solid, uniform circular disk. The heavier block is positioned a distance of 2.5m higher than the
lighter block, and they are released from rest. Assume the string does not slip across the surface of the pulley. Use mechanical energy conservation to find the speed of the blocks at the point when they swap positions (i.e. the heavier block is 2.5m lower than the lighter block)