Answer:
Two crates, A and B, are connected with a rope of negligible mass over a frictionless pulley as represented in the diagram shown on the left. The crates are at rest.
Crate A has an unknown mass and hangs vertically to the right of the slope and crate B, with mass 14 kg, hangs on the slope to the left. The slope makes and angle of 68° with the horizontal.
The coefficient of static friction between crate B and the surface of the slope is 0.3. The direction of the frictional force is up the slope. Calculate the mass of crate A.