A horizontal force F shown in the figure is exerted on a vertical lever to prevent a load (weight W) from falling downwards. The drum can rotate without friction about point B; the coefficient of static friction between the drum and the block is u0=D.30. Determine the magnitude of the force F (in kN) needed to prevent the drum from rotating. Use a=4m, b=3m, c=1m and diameter of drum is 4m.

A horizontal force F shown in the figure is exerted on a vertical lever to prevent a load (weight W) from falling downwards. The drum can rotate without friction about point B; the coefficient of static friction between the drum and the block is u0=D.30. Determine the magnitude of the force F (in kN) needed to prevent the drum from rotating. Use a=4m, b=3m, c=1m and diameter of drum is 4m.

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 7.72P

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