F4-20. If the coefficient of static friction at all contacting surfaces is , determine the inclination e at which the identical blocks, each of weight W, begin to slide.

Determine the maximum and the minimum values of weight W which may be applied without causing the 25-kg block to slip. The coefficient of static friction between the block and the plane is μs= 0.2, and between the rope and the drum D is μ′s= 0.3.

* Incorrect The 175-lb man with center of gravity G supports the 88-lb drum as shown. Find the greatest distance x at which the man can position himself without slipping if the coefficient of static friction between his shoes and the ground is 0.48. 14' 88 lb Answer: x = i 8.90 12.9¹ ft

The block weighs 80 pounds. A cable is connected to itsupper left corner and passes over a fixed post. Thecoefficients of friction are μB = 0.3 for the block and theground and μP = 0.2 for the post and the cable. Determinethe minimum force T that will cause the system to move(either tip or slide - you must show which happens first).Take a = 2.5’ and b = 6’.