Design a shaft to transmit power from a motor to a lathe head stock through a pulley by means of a belt drive. The pulley weighs 200 N and is located at 300 mm from the centre of the bearing. The diameter of the pulley is 200 mm and the power transmitted is 1 kW at 120 r.p.m. The angle of lap of the belt is 180° and coefficient of friction force between the belt and the pulley is 0.3. The shock and fatigue factors for twisting and bending are 1.5 and 2.0 respectively. The maximum shear stress in the shaft may be taken as 35 MPa.