The steel shaft (Gst = 10.8×103 ksi) is made from two segments: AC has a diameter of 0.5 in L=5in, and CDB has a diameter of 1 in Lcd=8 in Ldb=12 in. If it is fixed at its ends A and B and subjected to a torque of 500 lb-ft, determine:
a) The reaction Torques at A and B
b) The max shear stress in the shaft