Levitating Donut Magnet?

Most recent answer: 04/19/2017

Q:
We take a donnut magnet and hang it freely with a string and when it will come to a stable position we take a iron piece and try to find a stable point between magnetic force and gravitational force. So if we find that point will that iron piece levitate. If yes then HOW?
- Ayan Paul (age 16)
India
A:

There is no stable point for that system. The Earnshaw/Braunbeck  theorem shows that. 
https://en.wikipedia.org/wiki/Earnshaw%27s_theorem
https://en.wikipedia.org/wiki/Earnshaw%27s_theorem

Mike W.


(published on 04/19/2017)