The rack has a mass m = 75 kg. What moment M must be exerted by the gear wheel in order to (a) lower and (b) raise the rack at a slow steady speed on the greased 60° rail? The coefficients of static and kinetic friction are ls = 0.1 and µk motor which drives the gear wheel is not = 0.05. The fixed shown.

The rack has a mass m = 75 kg. What moment M must be exerted by the gear wheel in order to (a) lower and (b) raise the rack at a slow steady speed on the greased 60° rail? The coefficients of static and kinetic friction are ls = 0.1 and µk motor which drives the gear wheel is not = 0.05. The fixed shown.

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 7.81P: Calculate the horizontal force P required to push the 85-lb lawn mower at constant speed. The center...

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