A block with weight W is pulled up a plane forming an angle a with the horizontal by a force P directed along the plane. μ If is the coefficient of friction between the block and the plane, derive an expression for the mechanical efficiency of the system. Show that the mechanical efficiency cannot exceed 1/2 if the block is to remain in place when the force P is removed.

A block with weight W is pulled up a plane forming an angle a with the horizontal by a force P directed along the plane. μ If is the coefficient of friction between the block and the plane, derive an expression for the mechanical efficiency of the system. Show that the mechanical efficiency cannot exceed 1/2 if the block is to remain in place when the force P is removed.

International Edition---engineering Mechanics: Statics, 4th Edition

4th Edition

ISBN:9781305501607

Author:Andrew Pytel And Jaan Kiusalaas

Publisher:Andrew Pytel And Jaan Kiusalaas

Chapter7: Dry Friction

Section: Chapter Questions

Problem 7.66P: The blocks A and B of weights WA and WB are joined by a rope that passes over the fixed peg C. The...

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