A long thin rod of mass M = 2 kg and length L = 75 cm is free to rotate about its center as shown. Two identical masses (each of mass m = 0.853 kg) slide without friction along the rod. The two masses begin at the rod's point of rotation when the rod is rotating at 10 rad/s.
(a) When they have moved halfway to the end of the rod, how fast is the rod rotating?
(b) When the masses are halfway to the end of the rod, what is the ratio of the final rotational kinetic energy to the initial rotational kinetic energy (Krf /Kri )?
(c) When they reach the end, how fast is the rod rotating?