A student sits on a freely rotating stool holding two weights, each of mass 3.10 kilograms. When his arms are extended horizontally, the weights are 0.92 meter from the axis of rotation and he rotates with an angular speed of 0.747 rad/s. The moment of inertia of the student plus stool is 3.10 kg•m2 and is assumed to be constant. The student pulls the weights inward horizontally to a position 0.305 meter from the rotation axis.
(a) Determine the new angular speed of the student.
rad/s
(b) Determine the kinetic energy of the rotating system before and after he pulls the weights inward.
J (before)
J (after)