The force P is applied to the 68-kg block when it is at rest. Determine the magnitude and direction of the friction force exerted by the surface on the block if (a) P = 0, (b) P = 237 N, and (c) P = 416 N. (d) What value of P is required to initiate motion up the incline? The static and kinetic coefficients of friction between the block and the incline are μ = 0.25 and Uk = 0.22, respectively. The friction force is positive if up the incline, negative if down the incline. Answers: 68 kg 15° 24° H₂= 0.25 H₂ = 0.22

The force P is applied to the 68-kg block when it is at rest. Determine the magnitude and direction of the friction force exerted by the surface on the block if (a) P = 0, (b) P = 237 N, and (c) P = 416 N. (d) What value of P is required to initiate motion up the incline? The static and kinetic coefficients of friction between the block and the incline are μ = 0.25 and Uk = 0.22, respectively. The friction force is positive if up the incline, negative if down the incline. Answers: 68 kg 15° 24° H₂= 0.25 H₂ = 0.22

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 7.71P: The 600-lb cable spool is placed on a frictionless spindle that has been driven into the ground. If...

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