An electric motor is"driving" a machine in a textile factory with a "flat belt". The motor is delivering 1.25 hp at 1725 rpm to the machine and the coefficient of friction between the belt and the 3.5 in diameter steel pulley attached to the motor shaft is μ = 0.25. If the tension in the "tight side" of the flat belt is 54 lb, what is the minimum "angle of wrap" needed to prevent the flat belt from slipping on the motor pulley? Ans. 151.3°

An electric motor is"driving" a machine in a textile factory with a "flat belt". The motor is delivering 1.25 hp at 1725 rpm to the machine and the coefficient of friction between the belt and the 3.5 in diameter steel pulley attached to the motor shaft is μ = 0.25. If the tension in the "tight side" of the flat belt is 54 lb, what is the minimum "angle of wrap" needed to prevent the flat belt from slipping on the motor pulley? Ans. 151.3°

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 7.78P: The figure shows a steel bar being processed by a rolling mill. Given that P=80kN and r =0.016,...

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