4.As shown in the figure, a square threaded screw is used in a vise to exert a pressure of 2 tons. If the screw is double-threaded and has a pitch of 0.25 m and a mean radius of 1.5 inch, determine...

Extracted text: 4.As shown in the figure, a square threaded screw is used in a vise to exert a pressure of 2 tons. If the screw is double-threaded and has a pitch of 0.25 m and a mean radius of 1.5 inch, determine the torque that must be applied at B to create this pressure. Assume the coefficient of friction to be 0.15. P