An electric motor of mass 75 kg and speed 1200 rpm is mounted at the free end of a cantilevered steel beam of length 5 m, width 0.5 m and thickness of 0.1 m. A rotating force of magnitude F0 = 5000 N is developed due to the unbalance in the rotor of the motor. (Modulus of steel = 200 gpa)
a) Determine the natural frequency
b) Determine the amplitude of the steady state vibration if the mass of the beam is neglected.
c) What would be the amplitude if the force frequency was equal to the resonant frequency?