If the load of 4000 lb is lifted by the screw described in Problem 9 at the rate of 0.5 in/s, compute the required rotational speed of the screw and the power required to drive it.
Problem 9
If a square-thread screw having a major diameter of 3/4 in and six threads per inch is used to lift a load of 4000 lb, compute the torque required to rotate the screw. Use a co-efficient of friction of 0.15.