Chapter 8, Problem 94P

A 0.8 lb roll of paper is suspended from a wire hanger so that it rests against the wall.  The hanger has a negligible weight and the bearing O can be considered as frictionless.  The two ends of the hanger can be treated as pin joints.  Determine the force P required to start turning the roll if theta = 37 degrees and the coefficient of static friction is 0.29.

4. The mine car and its contents have a total mass of 6000 kg and a centre of gravity at G. If the coefficient of static friction 10 kN between the wheels and the 0.9 m •G tracks is u = 0.4 when the wheels are locked, find the normal force acting on the front wheels at B and the rear 0.15 m 0.6 m - 1.5 m wheels at A when the brakes at both A and B are locked. Does the car move? [Ans. NA = 16.5 kN, Ng =42.3 kN, the car does not move] %3D lyp

The disk clutch is used in standard transmissions of automobiles. If four springs are used to force two plates A and B together, determine the force in each spring required to transmit a moment of M = 600lb-ft across the plates. The coefficient of static friction between A and B is u, = 0.3.

The square-threaded screw has a mean diameter of 20 mm and a lead of 4 mm. If the weight of the plate A is 5 lb, determine the smallest coefficient of static friction between the screw and the plate so that the plate does not travel down the screw when the plate is suspended as shown.

The man pushes on the roller with force P through a handle that connects to the central axle of the roller. If the coefficient of static friction between the 49-lb roller and the floor is s = 0.22, determine the maximum force Pthat can be applied to the handle, so that roller rolls on the ground without slipping. Assume the roller to be a uniform cylinder. Please pay attention: the numbers may change since they are randomized. Your answer must include 2 places after the decimal point, and proper unit. Take g = 32.2 ft/s2. 1.5 ft 30° Your Answer: Answer units

The man pushes on the roller with force P through a handle that connects to the central axle of the roller. If the coefficient of static friction between the 43-lb roller and the floor is g = 0.16, determine the maximum force P that can be applied to the handle, so that roller rolls on the ground without slipping. Assume the roller to be a uniform cylinder. Please pay attention: the numbers may change since they are randomized. Your answer must include 2 places after the decimal point, and proper unit. Take g = 32.2 ft/s². Your Answer: Answer 30° units 1.5 ft

If the coefficient of static friction at C is μs = 0.35, determine the largest force F that can be appliedto the 3-kg ring, without causing it to slip. Neglect the thickness of the ring.

Determine the horizontal force P to start the 400-N wedge moving to the right. The angle of friction for all contact surfaces is o = 20°. WA = 2000 N WB = 400 N 15°

A 182 lb man climbs up the ladder and stops at the position shown when he senses the ladder is on the verge of slipping. Determine the coefficient of static friction between the ladder and the ground at A if the angle theta is 60 degrees. The ladder has a negligible weight and the wall at B is smooth. 3 ft- G 10 ft A