A merry-go-round modeled as a disk of mass M = 7.50 x 10- kg and radius R = 2.10 m is rotating in a horizontal plane about a frictionless vertical axle (see figure). (a) After a student with mass m = 82.0 kg jumps onto the merry-go-round, the system's angular speed decreases to 2.05 rad/s. If the student walks slowly from the edge toward the center, find the angular speed of the system when she reaches a point 0.470 m from the center. 5.88 rad/s (b) Find the change in the system's rotational kinetic energy caused by her movement to the center. 2073.05 (c) Find the work done on the student as she walks to r = 0.470 m. -2073.05 Your response differs from the correct answer by more than 100%. J

A merry-go-round modeled as a disk of mass M = 7.50 x 10- kg and radius R = 2.10 m is rotating in a horizontal plane about a frictionless vertical axle (see figure). (a) After a student with mass m = 82.0 kg jumps onto the merry-go-round, the system's angular speed decreases to 2.05 rad/s. If the student walks slowly from the edge toward the center, find the angular speed of the system when she reaches a point 0.470 m from the center. 5.88 rad/s (b) Find the change in the system's rotational kinetic energy caused by her movement to the center. 2073.05 (c) Find the work done on the student as she walks to r = 0.470 m. -2073.05 Your response differs from the correct answer by more than 100%. J

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 11P: A disk 8.00 cm in radius rotates at a constant rate of 1200 rev/min about its central axis....

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