See attached file.
Find the horizontal load P that will cause motion to the right, given coefficient of static friction for all surfaces is 0.33.© BrainMass Inc. brainmass.com March 4, 2021, 9:58 pm ad1c9bdddf
Let the tension in the strut is T, acting at an angle = 200 to the horizontal.
The forces acting on the lower block
(1) Its weight W1 = 50 lbs
(2) Normal reaction of the surface N1
(3) Tension of the strut T
(4) Applied force P
(5) The limiting friction force F1 = N1
The free body diagram is shown in the figure.
As the block is in limiting equilibrium, net force in horizontal direction should be zero. Resolving the tension T, its horizontal component will be T cos 200 to the left and hence writing equation of motion [F = ma] in horizontal direction we get
Two blocks are connected by a pinned rod, one on incline and one on horizontal surface. Force needed to push them up is calculated. Very good question to learn the force and equilibrium.