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Coil Levitation with Eddy Currents

I tried out a little quickie experiment in the lab this afternoon. In short: a coil with a changing current, (AC), placed on a non-ferromagnetic conductor, like aluminum, will induce an opposing magnetic field and levitate. You can read all about the effect caused by eddy currents, on Wikipedia, and watch what happened in the lab here:





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  1. UnknownMay 23, 2009 at 10:57 PM

    contd...

    in the circle?
    How many turns of copper wire? (just a guess of how much wire to use?

    If you could answer these I would be grateful.

    Lance

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  2. antigrav_kids KD0FNRJune 7, 2009 at 1:13 PM

    The power was 60Hz 120V regulated through a variac to about 30V. The coil is insulated magnet wire. I don't know, but I suspect there are about 300 turns. It's just an old coil I pulled out of the junk pile. The metal underneath is about 3/4 inch think aluminum.

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