8) A small block with a mass of 0.025 kg rests on a frictionless horizontal surface as shown in the figure. The block is attached to a cable passing through a hole on the surface. The block initially rotates at an angular velocity of 1.75 rad/s at a distance of 0.3 m from the hole. The cable is then pulled down to make the block turn over a radius of 0.15 m. Considering that the block is a point particle, (a) is the angular momentum of the block conserved? Explain. (b) Find the change in the kinetic energy of the block. (c) How much work is done by pulling the cable? Calculate.

8) A small block with a mass of 0.025 kg rests on a frictionless horizontal surface as shown in the figure. The block is attached to a cable passing through a hole on the surface. The block initially rotates at an angular velocity of 1.75 rad/s at a distance of 0.3 m from the hole. The cable is then pulled down to make the block turn over a radius of 0.15 m. Considering that the block is a point particle, (a) is the angular momentum of the block conserved? Explain. (b) Find the change in the kinetic energy of the block. (c) How much work is done by pulling the cable? Calculate.

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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