Lets say there is a pulley attached to the ceiling. Hanging on the pulley is a rope and on each end is a 1000 lb. weight. I believe that theoretically it wouldn't take any torque at all to rotate the pulley if it were frictionless (maybe inertia would play a role, but lets ignore that). However, in reality there will be a downward force on the pulley's shaft, causing friction. Lets say that a motor is connected to the pulley. I want to know if I turn the pulley, will the rope slip? My thoughts are that increasing weight will give better friction between the pulley and rope, and therefore, as long as the weights are equal, the torque required to rotate the pulley will be quite low, even though shaft friction increases as well with weight.