A 90.0-kg crate is being lowered off the roof of a building. Its rate of descent is slowed by a counterweight. The counterweight is a 65.0-kg weight on the roof of the building, connected to the crate by a steel cable passing over a pulley. The coefficient of kinetic friction between the roof material and the counterweight is 0.750. Assume the mass of the cable and friction in the pulley are negligible. At what rate will the crate being lowered accelerate downwards? What is the tension in the cable?

A 90.0-kg crate is being lowered off the roof of a building. Its rate of descent is slowed by a counterweight. The counterweight is a 65.0-kg weight on the roof of the building, connected to the crate by a steel cable passing over a pulley. The coefficient of kinetic friction between the roof material and the counterweight is 0.750. Assume the mass of the cable and friction in the pulley are negligible. At what rate will the crate being lowered accelerate downwards? What is the tension in the cable?

College Physics

10th Edition

ISBN:9781285737027

Author:Raymond A. Serway, Chris Vuille

Publisher:Raymond A. Serway, Chris Vuille

Chapter4: The Laws Of Motion

Section: Chapter Questions

Problem 60AP: (a) What is the minimum force of friction required to hold the system of Figure P4.74 in...

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