Problem 530 | Friction

Problem 530
A plank 10 ft long is placed in a horizontal position with its ends resting on two inclined planes, as shown in Fig. P-530. The angle of friction is 20°. Determine how close the load P can be placed to each end before slipping impends.
 

Plank resting horizontally on inclined planes

 

Problem 507 | Friction

Problem 507
The 2225-N block shown in Fig. P-507 is in contact with 45° incline. The coefficient of static friction is 0.25. Compute the value of the horizontal force P necessary to (a) just start the block up the incline or (b) just prevent motion down the incline. (c) If P = 1780 N, what is the amount and direction of the friction force?
 

Block on an incline pushed by horizontal force

 

Problem 309 | Equilibrium of Concurrent Force System Jhun Vert Sat, 04/18/2020 - 10:52 pm

Problem 309
A cylinder weighing 400 lb is held against a smooth incline by means of the weightless rod AB in Fig. P-309. Determine the forces P and N exerted on the cylinder by the rod and the incline.
 

A cylinder supported by a boom and an incline