Two A-36 steel pipes, each having a cross-sectional area of 0.32 in2, are screwed togeth...

Two A-36 steel pipes, each having a cross-sectional area of 0.32 in², are screwed together using a union at B as shown. Originally the assembly is adjusted so that no load is on the pipe. If the union is then tightened so that its screw, having a lead of 0.15 in., undergoes two full turns, determine the average normal stress developed in the pipe. Assume that the union at B and couplings at A and C are rigid. Neglect the size of the union. Note: The lead would cause the pipe, when unloaded , to shorten 0.15 in. when the union is rotated one revolution.