4. A person of mass 75 kg stands at the center of a rotating merry-go-round platform of radius 3.0 m and moment of inertia of 820 kgm?. The platform rotates without friction at an angular velocity of 0.95 rad/s. The person walks radially towards the edge of the platform. Calculate the following; a) the angular velocity when the person reaches the edge. b) the rotational kinetic energy of the system (platform and person) before and after the person walks. (Assume the person acts like a point mass.)

4. A person of mass 75 kg stands at the center of a rotating merry-go-round platform of radius 3.0 m and moment of inertia of 820 kgm?. The platform rotates without friction at an angular velocity of 0.95 rad/s. The person walks radially towards the edge of the platform. Calculate the following; a) the angular velocity when the person reaches the edge. b) the rotational kinetic energy of the system (platform and person) before and after the person walks. (Assume the person acts like a point mass.)

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 46P: A playground merry-go-round of radius R = 2.00 m has a moment of inertia I = 250 kg m2 and is...

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Suppose a child gets off a rotating merry-go-round, Does the angular velocity of the merry-go-round increase, decrease, or remain the same if: (a) He jumps off radially? (b) He Jumps backward to land motionless? (c) He jumps straight up and hangs onto an overhead tree branch? (d) He jumps off forward, tangential to the edge? Explain your answers. (Refer to Figure 10.34).
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