An aluminium tube has inside diameter d1 = 50 mm, shear modulus of elasticity G = 27

Question:

An aluminium tube has inside diameter d1 = 50 mm, shear modulus of elasticity G = 27 GPa, and torque T = 4.0 kN ( m. The allowable shear stress in the aluminum is 50 MPa and the allowable normal strain is 900 ( 10-6.
Determine the required outside diameter d2.