A hollow rectangular thin-wall steel torsion member has the cross section shown in Figure...

A hollow rectangular thin-wall steel torsion member has the cross section shown in Figure P6.55. The steel has a yield stress Y = 360 MPa and a shear modulus of elasticity of G = 77.5 GPa. Determine the maximum torque that may be applied to the torsion member, based on a factor of safety of SF = 2.00 for the octahedral shear stress criterion of failure. What is the unit angle of twist when the maximum torque is applied?

FIGURE P6.55