Gere & Goodno — Torsion: Problem 3.11-8

3.11-8 Calculate the shear stress \(\tau\) and the angle of twist \(\phi\) (in degrees) for a steel tube (\(G = 76\text{ GPa}\)) having the cross section shown in the figure. The tube has length \(L = 1.5\text{ m}\) and is subjected to a torque \(T = 10\text{ kN}\cdot\text{m}\). [Geometric parameters from figure: \(r = 50\text{ mm}\), \(b = 100\text{ mm}\), \(t = 8\text{ mm}\)]