The pulley of Fig. wheel that fits loosely over a t in.-diameter shaft. A rope passes over the pulley and is attached to a 50-lb weight. The static and kinetic coefficients of friction between the consists of a 4-in.-diameter pulley and the shaft are 0.35 and 0.25, respectively. The weight of the pulley is 2 lb. The rope being pulled makes an angle e = 90° with the horizontal. Determine the force necessary to Lower the weight at a constant speed. P

The pulley of Fig. wheel that fits loosely over a t in.-diameter shaft. A rope passes over the pulley and is attached to a 50-lb weight. The static and kinetic coefficients of friction between the consists of a 4-in.-diameter pulley and the shaft are 0.35 and 0.25, respectively. The weight of the pulley is 2 lb. The rope being pulled makes an angle e = 90° with the horizontal. Determine the force necessary to Lower the weight at a constant speed. P

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 7.57P: The square-threaded screw with a pitch of 10 mm and a mean radius of 18 mm drives a gear that has a...

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