A learner sits on a rotating stool holding two 3.0 kilogram objects. When his arms are extended horizontally, the objects are 1.0 meter from the axis of rotation and he rotates with an angular speed of 0.75rad/s. The moment of inertia of the student plus stool is 3.0 kg•m2 and is assumed to be constant. The student then pulls the objects horizontally to 0.50 meter from the rotation axis.
(a) Evaluate what the new angular speed of the learner.
(b) Evaluate the kinetic energy of the student before and after the objects are pulled.
before J
after J