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A student sits on a stool that is free t...

A student sits on a stool that is free to rotate about a vertical axis. He holds out his arms horizontally, with a 4-kg weight in each hand. The stool is set in rotation with angular speed of 0.5 revolution per second. Calcualate the angular speed of the student is 90 cm and his rotational inertia is 7kg `m^(2)`.
[Hint: Use conservation principle]

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The correct Answer is:
0.96 rev/sec.
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