-english is not my first language-
Edit: alot of people think im referring to motors or generators or some sorts. But I mean something like this:
https://i.ytimg.com/vi/BSdSDfOWbNs/maxresdefault.jpg
I know its probably fake and not possible but I want to know why and how
In: 0
I can take a magnet and put it on a shaft. Will it spin? No, because there is nothing pushing it around. So I place a magnet nearby, with its north pole facing the north pole of the magnet on the shaft. The poles repel and so the free magnet rotates to move its north pole away. Hooray! But after half a turn the south pole of the rotating magnet is facing the north pole of the fixed magnet, so they attract. What happens as the rotating magnet passes beyond half a turn? Instead of being pushed further round, it is actually slowed down by the attraction and so comes to a halt.
Could we get round this by reversing the fixed magnet? Yes we could – by flipping it round or by making it an electromagnet and reversing the current. The problem is that we are doing these things near to that rotating magnet. Just as the rotating magnet is pulled and pushed by the fixed magnet, the fixed magnet is pulled and pushed by the rotating magnet. To flip it round takes some effort, and in fact it takes exactly the same amount of effort as the amount of energy you get out of the spinning magnet. It is a bit harder to explain why using an electromagnet also results in putting just as much energy in as you get out: this exactly what we do in a motor.
Anyway, the simple answer is: r/ThatsPerpetualMotion
Latest Answers