Problem - A solid steel bar diameter d1 = 25.0 mm is enclosed by a steel tube of outer diameter d3 = 37.5 mm and inner diameter d2 = 30.0 mm. Both bar and tube are held fixed by a support at end A and joined securely to a rigid plate at end B. The composite bar, which has a length L = 550 mm, is twisted by a torque T = 400 Nm acting on the plate. Assuming the shear stress of steel is G = 80 GP.
(a) Determine the maximum shear stress in the bar and in the tube.
(b) Determine the angle of rotation φ of the end plate.
