Original upload date: Thu, 29 May 2008 00:00:00 GMT
Archive date: Sun, 05 Dec 2021 23:41:47 GMT
Eddy Current Tubes -- Drop the Magnets down the tube. An eddy current is set up in a conductor in response to a changing magnetic field. Lenz's law predicts that the current moves in such a way as to
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create a magnetic field opposing the change; to do this in a conductor, electrons swirl in a plane perpendicular to the changing magnetic field.
Because the magnetic fields of the eddy currents oppose the magnetic field of the falling magnet; there is attraction between the two fields. Energy is converted into heat. This principle is used in damping the oscillation of the lever arm of mechanical balances.