A steel bar (G=200 GPa) of cross section as shown in Fig. P6.29 is subjected to a torque...

A steel bar (G=200 GPa) of cross section as shown in Fig. P6.29 is subjected to a torque of 500 N.m. Determine the maximum shearing stress and the angle of twist per unit length. The dimensions are b₁=100 mm, b₂ = 125 mm, t₁ = 10 mm, and t₂ = 4 mm.