A boy of mass m= 36 kg is standing initially at rest relative to the moving walkway, which has a constant horizontal speed u = 1.1 m/s. He decides to accelerate his progress and starts to walk from point A with a steadily increasing speed and reaches point B (a distance s = 29 m) with a speed dx/dt = v = 2.5 m/s relative to the walkway. During his acceleration he generates an average horizontal force F between his shoes and the walkway. Calculate the work done on the boy by the force F from an absolute viewpoint and then from a relative viewpoint. Explain the difference. u A. B Answers: Absolute viewpoint, Work = i Relative viewpoint, Work = i

A boy of mass m= 36 kg is standing initially at rest relative to the moving walkway, which has a constant horizontal speed u = 1.1 m/s. He decides to accelerate his progress and starts to walk from point A with a steadily increasing speed and reaches point B (a distance s = 29 m) with a speed dx/dt = v = 2.5 m/s relative to the walkway. During his acceleration he generates an average horizontal force F between his shoes and the walkway. Calculate the work done on the boy by the force F from an absolute viewpoint and then from a relative viewpoint. Explain the difference. u A. B Answers: Absolute viewpoint, Work = i Relative viewpoint, Work = i

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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