i posted it in general physics and got not answer. maybe this is the right place for this. thanks here is a question for max dynamic factor for sinusoidal load F*sin(at). say the natural frequency is b for a mass. then the max DLF considering damping is DLF=1/(1-(a/b)^2) when a>>b DLF=0 what does that mean in the reality. it means if you apply a dynamic load with very very high frequency to a mass. the mass don't get any force? how come? why? thanks a lot.