2.1 MEG QuickTime File.
Even a ring with zero resistance cannot levitate a magnet which is too heavy, or which is moving too fast when it approaches the ring. The magnet falls through. However, the magnetic flux through the ring (that of the magnet plus that of the ring) cannot change. In this case the magnet started far from the ring, so that there was little flux through the ring to begin with. However, that same (little) flux through the ring is still there after the magnet has fallen through, but it is provided by eddy currents in the ring at large times. In this case the current in the ring never changes direction as the magnet falls through--it repels the magnet when it is above the ring and it repels it when it is below the ring.
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