A mass of 1kg rests on a horizontal table. It is connected by a taut, light, inextensible string passing over a smooth fixed pulley, at the edge of the table, to another mass of 3kg hanging vertically. The 3kg mass it at a height of 0.5 metres above an inelastic floor when the system is released from rest. There is also a frictional resistance to the motion from the table of 0.5 N. Determine the total work done by the frictional force, assuming that the 1kg mass stop before reaching the pulley. I've included a diagram I drew. Im not quite sure where to go with this question. Could you help me out? The answer i'm looking for is 3.8625 J.