2. A winch is a mechanical lifting or hauling device consisting of a rope, cable, or chain winding around a horizontal rotating drum, turned by a crank or by motor or other power source. We use one at our cottage to move heavy things like fallen trees. a) A motor on an electric winch is only 45% efficient. How much work must be done to winch a 200 kg load of bricks up 4 floors on a construction site if each floor is 4.0 m? b) What power must the motor generate to accomplish this in 42 s?

2. A winch is a mechanical lifting or hauling device consisting of a rope, cable, or chain winding around a horizontal rotating drum, turned by a crank or by motor or other power source. We use one at our cottage to move heavy things like fallen trees. a) A motor on an electric winch is only 45% efficient. How much work must be done to winch a 200 kg load of bricks up 4 floors on a construction site if each floor is 4.0 m? b) What power must the motor generate to accomplish this in 42 s?

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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