A hollow shaft and a solid shaft constructed of the same material have the same length and the same outside radius. The inside radius of the hollow shaft is 0.6 times of the outside radius. Both the shafts are subjected to the same torque.
(i) What is the ratio of maximum shear stress in the hollow shaft to that of solid shaft?
(ii) What is the ratio of angle of twist in the hollow shaft to that of solid shaft?