A student sits on a freely rotating stool holding two dumbbells, each of mass 3.08 kg (see figure below). When his arms are extended horizontally (Figure a), the dumbbells are 0.97 m from the axis of rotation and the student rotates with an angular speed of 0.741 rad/s. The moment of inertia of the student plus stool is 2,59 kg • m? and is assumed to be constant. The student pulls the dumbbells inward horizontally to a position 0.307 m from the rotation axis (Figure b). (a) Find the new angular speed of the student. rad/s (b) Find the kinetic energy of the rotating system before and after he pulls the dumbbells inward. Kbefore = Kafter

A student sits on a freely rotating stool holding two dumbbells, each of mass 3.08 kg (see figure below). When his arms are extended horizontally (Figure a), the dumbbells are 0.97 m from the axis of rotation and the student rotates with an angular speed of 0.741 rad/s. The moment of inertia of the student plus stool is 2,59 kg • m? and is assumed to be constant. The student pulls the dumbbells inward horizontally to a position 0.307 m from the rotation axis (Figure b). (a) Find the new angular speed of the student. rad/s (b) Find the kinetic energy of the rotating system before and after he pulls the dumbbells inward. Kbefore = Kafter

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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