1. The double pulley shown is attached to a 8-mm-radius shaft that fits loosely in a fixed bearing. If the μ = 0.45 and μ = 0.40 and the weight of the pulley is 25 N, (a) determine the magnitude of the force P required to start raising the load, and (b) determine the magnitude of the force P required to start lowering the load a constant speed. 90 mm 45 mm Ý CI P 20 kg

1. The double pulley shown is attached to a 8-mm-radius shaft that fits loosely in a fixed bearing. If the μ = 0.45 and μ = 0.40 and the weight of the pulley is 25 N, (a) determine the magnitude of the force P required to start raising the load, and (b) determine the magnitude of the force P required to start lowering the load a constant speed. 90 mm 45 mm Ý CI P 20 kg

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 7.79P: The coefficient of rolling resistance between the 30-kg lawn roller and the ground is r=0.1. (a)...

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