One end of a light string is slipped around a peg fixed in a horizontal table top, while the other end is tied to a 0.5 kg small disc. The disc is given an initial velocity of magnitude `3.4m//s` so that it moves in a horizontal circle of radius 0.75 m. The object comes to rest after 2.5 revolutions (a) For the entire motion, what work is done by the frictional force ? (b) Assume that the magnitude of the frictional force is constant and determine the coefficient of kinetic friction at the interface (c) Determine the tension in the string at the instant that the disc completes the first revolution (d) How much work is done by the tension in the string ?

Answer

B, D