Question: A machine of mass M rests on a massless elastic floor, as shown in Fig. If a unit load is applied at midspan, the floor undergoes a deflection xst. A shaker having total mass in and carrying two rotating unbalanced masses (similar to the rotating mass shown in Fig. 1.34a) produces a vertical harmonic force mlω2 sin cot, where the frequency of rotation can vary. Show how the shaker can be used to derive a formula for the natural frequency of flexural vibration of the structure.
