Two identical twins hold on to a rope, one at each end, on a smooth, frictionless ice surface. they skate in a circle about the center of the rope (the center of mass of the two-body system) and perpendicular to the ice. the mass of each twin is 78.0 kg. the rope of negligible mass is 4.0 m long and they move at a speed of 4.30 m/s.
(a) what is the magnitude, in kg · m2/s, of the angular momentum of the system comprised of the two twins?
· m2/s.
(b) they now pull on the rope and move closer to each other so that the rope between them is now half as long. determine the speed, in m/s, with which they move now.
/s.
(c) the two twins have to do work in order to move closer to each other. how much work, in joules, did they do?
.