Take the 2-minute tour ×
Physics Stack Exchange is a question and answer site for active researchers, academics and students of physics. It's 100% free, no registration required.

If you were to build an upright machine that had a rod fitted into a ball bearing at the base and was secured to another rod at the top of the initial rod extending perpendicularly. To which you attached a magnet, and around this machine you also placed several upright rods containing magnets that would push/pull the magnet attached to the rod, would this cause the initial magnet to spin the machine for some period of time?

(Assuming I'm giving the machine a push to start the motion initially)

Inevitably, provided the above would work, friction would lead to an eventual slowing. With that said is there anyway to postpone that slowing for a reasonable period of time? Can magnetic shielding be used in any fashion to maintain the motion for longer?

share|improve this question
    
are you giving it an initial push to get going? –  Jim Apr 26 '13 at 22:15
    
Yes I suppose it won't work otherwise, not without some kind of motor or battery anyway. –  DeeplyConfused Apr 26 '13 at 22:21
    
In that case, I think what you're describing is essentially a magnetic bearing. –  Jim Apr 26 '13 at 22:28
    
So this will work then? Certainly not indefinitely, but for a period of time without me having to play with it? Ideally this machine is spinning for a reasonable amount of time- is that too possible? –  DeeplyConfused Apr 26 '13 at 22:31
    
I think the magnets may need to be powered and alternating in direction, otherwise they would increase resistance rather than decrease it. But I could be wrong; I'm sure the internetz could elaborate more about mag bearings –  Jim Apr 26 '13 at 22:37

Your Answer

 
discard

By posting your answer, you agree to the privacy policy and terms of service.

Browse other questions tagged or ask your own question.