Problem 1.124

A chain of mass \(m=0.80 \mathrm{~kg}\) and length \(l=1.5 \mathrm{~m}\) rests on a rough-surfaced table so that one of its ends hangs over the edge. The chain starts sliding off the table all by itself provided the overhanging part equals \(\eta=1 / 3\) of the chain length. What will be the total work performed by the friction forces acting on the chain by the moment it slides completely off the table?