A student sits on a rotating stool holding two 2 kg objects. When his arms are extended horizontally, the objects are 0.9 m from the axis of rotation, and he rotates with angular speed of 0.74 rad/sec. The moment of inertia of the student plus the stool is 7 kg m2 and is assumed to be constant. The student then pulls the objects horizontally to a radius 0.28 m from the rotation axis.
(a) Find the new angular speed of the student.
rad/s
(b) Find the kinetic energy of the student before and after the objects are pulled in.
before: J
after: J
Answers: 1
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A student sits on a rotating stool holding two 2 kg objects. When his arms are extended horizontally...