A man stands on a platform that is rotating (without friction) with an angular speed of 0.618 rev/s; his arms are outstretched and he holds a brick in each hand. The rotational inertia of the system consisting of the man, bricks, and platform about the central axis is 6.20 kg-m2. If by moving the bricks the man decreases the rotational inertia of the system to 1.66 kg-m², (a) what is the resulting angular speed of the platform and (b) what is the ratio of the new kinetic energy of the system to the original kinetic energy? (a) Number i Units (b) Number i Units

A man stands on a platform that is rotating (without friction) with an angular speed of 0.618 rev/s; his arms are outstretched and he holds a brick in each hand. The rotational inertia of the system consisting of the man, bricks, and platform about the central axis is 6.20 kg-m2. If by moving the bricks the man decreases the rotational inertia of the system to 1.66 kg-m², (a) what is the resulting angular speed of the platform and (b) what is the ratio of the new kinetic energy of the system to the original kinetic energy? (a) Number i Units (b) Number i Units

Principles of Physics: A Calculus-Based Text

5th Edition

ISBN:9781133104261

Author:Raymond A. Serway, John W. Jewett

Publisher:Raymond A. Serway, John W. Jewett

Chapter10: Rotational Motion

Section: Chapter Questions

Problem 50P: A disk with moment of inertia I1 rotates about a frictionless, vertical axle with angular speed i. A...

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