A student sits on a freely rotating stool holding two dumbbells, each of mass 2.90 kg (see figure below). When his arms are extended horizontally (Figure a), the dumbbells are 1.02 m from the axis of rotation and the student rotates with an angular speed of 0.758 rad/s. The moment of inertia of the student plus stool is 2.70 kg m2 and is assumed to be constant. The student pulls the dumbbells inward horizontally to a position 0.297 m from the rotation axis (Figure b). b (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 dumbbells inward. Kbefore Kafter J J