|A disk with moment of inertia I1 rotates about a frictionless, vertical axle with angular speed Wi. A second disk, this one having moment of inertia I2 and initially not rotating, drops onto the first disk (see figure below). Because of friction between the surfaces, the two eventually reach the same angular speed wf. (a) Calculate wf. (b) Calculate the ratio of the final to the initial rotational energy. Before After

|A disk with moment of inertia I1 rotates about a frictionless, vertical axle with angular speed Wi. A second disk, this one having moment of inertia I2 and initially not rotating, drops onto the first disk (see figure below). Because of friction between the surfaces, the two eventually reach the same angular speed wf. (a) Calculate wf. (b) Calculate the ratio of the final to the initial rotational energy. Before After

College Physics

11th Edition

ISBN:9781305952300

Author:Raymond A. Serway, Chris Vuille

Publisher:Raymond A. Serway, Chris Vuille

Chapter1: Units, Trigonometry. And Vectors

Section: Chapter Questions

Problem 1CQ: Estimate the order of magnitude of the length, in meters, of each of the following; (a) a mouse, (b)...

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