Thanks for sharing the videos. I like the two videos explaining resonance. You can easily understand the concept behind how vibration can manifest in a body due to coupling of two coincident frequencies (the frequency of the source and the natural frequency of a body). Especially the first video where it shows that as long as you have a good separation between the source frequency and natural frequency of the body, vibration will be eliminated if not minimized.
Cheers!!!
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Borzki