What are some simple experiments for inexperienced hobbyists to try?

[StarEagle1]

How did you find PF?

I was searching for rotation and counterweight

I am sort of a hobbyist. I have only wanted to be an inventor or engineer since I was young, but circumstances said otherwise and I somewhat forgot about it. I had a high assessment for mechanical ability when I joined the Navy, so I became a Aviation Structural Mechanic (Hydraulics). I have done some very simple experiments, but these days I don't have much time except to think about new ideas for simple devices. I hope to retire in around a year and start doing more experiments

 

[PeroK]