A 36-lb motor is bolted to a light horizontal beam which has a static deflection of 0.075 in. due to the weight of the motor. Knowing that the unbalance of the rotor is equivalent to a weight of 0.64 oz located 6.25 in. from the axis of rotation, determine the amplitude of the vibration of the motor at a speed of 900 rpm, assuming

(a) That no damping is present,

(b) That the damping factor c/cc is equal to 0.055.