Two friends hold on to a rope, one at each end, on a smooth,frictionless ice surface. They skate in a circle about an axisthrough the center of the rope and perpendicular to the ice. Themass of one friend is 81.0 kg and the other has a mass of 125.0 kg.The rope of negligible mass is 4.5 m long and they move at a speedof 4.50 m/s.
(a) What is the magnitude of the angular momentum of the systemcomprised of the two friends? kg · m2/s
(b) They now pull on the rope and move closer to each other sothat the rope between them is now half as long. Determine the speedwith which they move now. m/s
(c) The two friends have to do work in order to move closer toeach other. How much work did they do? J
