Here is a thought I had. I am sure it won't work. But can you tell me why?
1. In a vacuum - if you push something, it'll keep on moving because of lack of friction / law of inertia - correct?
2. So can you push a rotor in a vacuum so that it always keeps on moving on its hinges and keeps on generating electrical power - which can be stored in batteries?
So even if you could make it go around perpetually you wouldn't generate energy just from that.
It's kind of like lighting a match.
You can sway it around in the air, but it is not until you actually put it down on the match box that you start creating energy.
Now the trick is to create energy to both keep dragging your match along the box and at the same time generation som energy surplus.
Pardon my ignorance.
I read about entropy on wikipedia. But didn't get a clear picture about it.
Does it mean that because of entropy - the rotor in a vacuum will stop movement?
(What I'm curious about is: "A thing in motion keeps on moving at the same speed in a vacuum" - is that an incorrect statement?)
OK - you have spotted that drag from air can quickly slow down an object here on earth and that thus an object in a vacuum will spin (or whatever) for a lot longer without air slowing it down.
But drag from air is not the only force likely to affect the motion of your theoretical object.