# Physics: Rotation Example 2

**Question description**

A student sits on a rotating stool holding two 3.5-kg objects. When his arms are extended horizontally, the objects are 1.0 m from the axis of rotation and he rotates with an angular speed of 0.75 rad/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 in the objects horizontally to 0.40 m from the rotation axis.

(a) Find the new angular speed of the student. (b) Find the kinetic energy of the student before and after the objects are pulled in.

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