Solve the below problem:
Q: A vibrometer used to measure the amplitude of vibrations consists of a box containing a mass-spring system with a known natural frequency of 150 Hz. The box is rigidly attached to a surface which is moving according to the equation y = dm sin ωft. If the amplitude zm of the motion of the mass relative to the box is used as a measure of the amplitude dm of the vibration of the surface, determine
(a) The percent error when the frequency of the vibration is 750 Hz,
(b) The frequency at which the error is zero.