A solid circular steel shaft is encased in a hollow copper shaft so as to make a compound shaft. The diameter of the steel shaft is 8 cm and the outside diameter of the copper shaft is 11 cm. The compound shaft of length 2 m is subjected to an axial torque of 8 kNm. Determine the maximum shear stress in steel and copper.
Given : Gsteel = 2 Gcopper = 80 kN/mm2