The weight of the block in the drawing is 95.3 N. The coefficient of static friction between the block and the vertical wall is 0.540.
(a) What minimum force F is required to prevent the block from sliding down the wall? (Hint: The static frictional force exerted on the block is directed upward, parallel to the wall.)
(b) What minimum force is required to start the block moving up the wall? (Hint: The static frictional force is now directed down the wall.)