A child of mass m = 40 kg is initially placed on the edge of a uniform disk, of mass M = 100 kg and radius R = 2.0 m, which is rotating with an angular speed w_i about a vertical axis passing through its center. The child moves on a radius and stops at the distance a = 1.5 m from the edge of the disk as indicated. If the final angular speed of the disk-child system is w_f= 4.5 rad/s, determine the initial angular speed w_i. Wf a m

A child of mass m = 40 kg is initially placed on the edge of a uniform disk, of mass M = 100 kg and radius R = 2.0 m, which is rotating with an angular speed w_i about a vertical axis passing through its center. The child moves on a radius and stops at the distance a = 1.5 m from the edge of the disk as indicated. If the final angular speed of the disk-child system is w_f= 4.5 rad/s, determine the initial angular speed w_i. Wf a m

Physics for Scientists and Engineers: Foundations and Connections

1st Edition

ISBN:9781133939146

Author:Katz, Debora M.

Publisher:Katz, Debora M.

Chapter13: Rotation Ii: A Conservation Approach

Section: Chapter Questions

Problem 47PQ

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