1.During the manufacturing process, a circular steel bar of diameter20mm and length of 1.2m is subjected to an axial load P. Themodulus of elasticity of steel is 207 GPa. The steel bar mustacquire an elastic strain energy of 14J. Find yield strengthfor a factor of safety of 3 with respect to plasticdeformation.
2.Two shafts are made of the same material and are of equal lengths.one of them is solid and another one is hollow. the ratio ofinside and outside diameters for hollow shaft is 0.65. They are subjected to the same torque and same maximum shearstress. Determine the ratio (Ws/ Wh) of the weight of the solid shaft (Ws) to the weight of the hollow shaft (Wh)