A bar of mild steel has a diameter of 75 mm and is placed inside a hollow aluminum cylinder ofinternal diameter 75 mmand external diameter 100 mm; both bar and cylinder are the same length. Theresulting composite bar is subjected to an axial compressive load of 1000 kN. If the bar and cylindercontract by the same amount, calculate the stress in each. The temperature of the compressed compositebar is then reduced by 150Cbut no change in length is permitted. Calculate the final stress in the bar and the cylinder if E(steel)= 200,000 N/mm^2, E(aluminum)= 80,000 N/mm^2, coefficient of linear expansion for steel= 0.0000012/C and coefficient of linear expansion for aluminum= 0.000005/C.