A 1/8" radius steel rod that is 2 ft long has a 20,000 in-lbs external torque
applied. [J = (T4)/2]
A. What is the polar moment of inertia for the rod?
B. If the Modulus of Rigidity for the steel bar is 18 X 10³ Ksi, what is the
expected twist of the bar in degrees?
Fig: 1