It was suggested that for a particular rotor system, the main shaft which is a solid shaft, could be replaced by a hollow shaft, keeping their length at 0.5m. The solid shaft has a diameter of 20mm. The hollow shaft has OD=25mm and ID 15mm. A torque of 1500Nm is applied to each of the two shafts

i. Calculate the angle of twist (in degrees) of each of the shaft.

ii. Calculate the maximum torsional shear stress for each of the shafts