A shaft 100 mm diameter (D) runs in a bearing 200 mm long (L). The two surfaces are separated by an oil film 2.5 mm thick (c). Take the oil viscosity (u) as 0.25 kg/ms. if the shaft rotates at a speed of (N) revolutions per minute. a) Show that the torque exerted on the bearing is given as: uXn x.NxL xD Torque = 120xc b) Calculate the torque necessary to rotate the shaft at 600 rpm.