Resonace of the system
 

Hi Friends, it may be wrong place to keep my question. But being it is a mechanical eng problem , i am posting this question in this forum . my question is let us imagine that a ''sinus signal'' is made to pass throuhg one mechanical system and out put siganl is capture. when this system is reached to resonance frequency, the amplitude and force signal of the out put is incresed. based on the input signals and output signals i calculated WORK_INPUT and WORK_OUTPUT, and POWER_INPUT and POWER_OUTPUT, it was found as WORKOUT and POWEROUT is much higher than corresponding input values,, i, e this systems efficiency is more than 100%.. please i am very confusing with this results,,I am kindly requesting to know ur views ,,

thankou