A student sits on a freely rotating stool holding two weights, each of mass 2.90 kg. When his arms are extended horizontally, the weights are 0.94 m from the axis of rotation and he rotates with an angular speed of 0.760 rad/s. The moment of inertia of the student plus stool is 2.90 kg·m2 and is assumed to be constant. The student pulls the weights inward horizontally to a position 0.292 m from the rotation axis.
(a) Find the new angular speed of the student.
rad/s
(b) Find the kinetic energy of the rotating system before and after he pulls the weights inward.
J (before)
J (after)