A short demonstration of static and dynamic balance or unbalance, with a short explanation of how both phenomena arise. I highly recommend you give this a try for yourself, because feeling it is really much better than seeing it. The Fusion360 file can be found here:

https://creonovae-my.sharepoint.com/:...

If you can't use Fusion360 and you need .stl files, you can find them here: https://www.thingiverse.com/thing:479...