Forced Vibration (damped, undamped)

Therefore, the ratio is often called the magnification factor and depends on . Plots of magnification factor versus have been shown for three values of damping factor. When the damping is very small the magnification factor is very large in the vicinity of natural frequency. Hence, the forcing frequency should not be close to natural frequency, if the vibrations have to be avoided. One can seen that for large value of , the magnification factor becomes very small. Hence, the operating (forcing) frequency should be 4-5 times the natural frequency for best results.