•• P28 A string is wrapped around a disk of mass 2.1 kg (its density is not necessarily uniform). Starting from rest, you pull the string with a constant force of 9 N along a nearly frictionless surface. At the instant when the center of the disk has moved a distance 0.11 m, your hand has moved a distance of 0.28 m (Figure 9.51). 2.1 kg 9N 0.11 m 9N 0.28 m Figure 9.51 (a) At this instant, what is the speed of the center of mass of the disk? (b) At this instant, how much rotational kinetic energy does the disk have relative to its center of mass? (c) At this instant, the angular speed of the disk is 7.5 rad/s. What is the moment of inertia of the disk?

•• P28 A string is wrapped around a disk of mass 2.1 kg (its density is not necessarily uniform). Starting from rest, you pull the string with a constant force of 9 N along a nearly frictionless surface. At the instant when the center of the disk has moved a distance 0.11 m, your hand has moved a distance of 0.28 m (Figure 9.51). 2.1 kg 9N 0.11 m 9N 0.28 m Figure 9.51 (a) At this instant, what is the speed of the center of mass of the disk? (b) At this instant, how much rotational kinetic energy does the disk have relative to its center of mass? (c) At this instant, the angular speed of the disk is 7.5 rad/s. What is the moment of inertia of the disk?

College Physics

11th Edition

ISBN:9781305952300

Author:Raymond A. Serway, Chris Vuille

Publisher:Raymond A. Serway, Chris Vuille

Chapter5: Energy

Section: Chapter Questions

Problem 86AP: Two blocks, A and B (with mass 50.0 kg and 1.00 102 kg, respectively), are connected by a string,...

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