1. A constant force Fa pushes on a block of mass m that is placed against a vertical wall, as shown in the figure below. The force makes an angle of o with the vertical and the coefficients of friction between the block and the wall are #, and #x. In terms of m. 0, the coefficients of friction, and physical constants, what is the maximum magnitude with which the force can push on the block while it remains stationary on the wall? 2. A box of mass m = 15.0 kg is initially at rest at the bottom of a rough plane that is inclined at an angle of # = 30.0 above the horizontal. You push horizontally on the box with a constant force Fa that has a magnitude of 180 N. As you push, the box accelerates up the incline at a rate of 0.450 m/s?. What is the coefficient of kinetic friction between the box. and the plane? Fa 3. A 4.5-kg block rests on a rough horizontal table with a rope attached to it. The coefficient of static friction between the block and the table is 0.400 and the coefficient of kinetic friction between the block and the table is 0.380. The rope is pulled at an angle of 35.0" above the horizontal. (a) What is the hardest you can pull on the rope while the block remains stationary on the table? (b) What is the magnitude of the block's acceleration if you pull on the rope with a force 1.25 times greater than your answer in part (a)? 4. Two boxes are connected by a massless rope the runs across a massless frictionless pulley. A box with mass mi = 2.00 kg rests on a frictionless horizontal surface. A second box with mass my = 3.00 kg lies on a frictionless surface inclined at an angle of 0 = 30.0 above the horizontal. A force with a magnitude of |F. | = 20.0 N pulls the set of boxes. (a) What is the magnitude of the acceleration of the two boxes? (b) What is the magnitude of the tension in the rope