Re: The Levitron; Overunity in a box?

Djsquires@aol.com
Sat, 12 Dec 1998 21:40:31 EST

Of course you don't feel anything if you just run a piece of wire
past a magnet. The eddy currents are too small and the motion
is not very fast. If you were to short out a loop it would be a bit
better, but not much. This is a moot discussion since the flux
lines would not be cutting across the copper in the case of
a levitron in a vacuum. In math terms there is no delta-B.

If you want to see the effect I speak of take a strong neodymium
magnet and drop it down an aluminum plate or piece of channel
at a steep angle. You will see that it slides very slowly due to
eddy currents generated that create a field that opposes the motion.
This is the flux coupling that would resist the motion and stop a
freely spinning magnet. This happens because the sheet of metal
acts like a shorted generator.

A levitron might spin for a very long time in a vacuum perhaps even
forever if left alone, but it would just be a lab curiosity. You could never
pull any power from it.

Sorry to burst your bubble. But keep an open mind and do your homework.

Regards,
Dave Squires