Tuesday, April 28, 2009

Magnet + Copper Tube = Eddy Current

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 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.

1 comment:

Tattoo Jim said...

There's going to be a lot of magnets and copper pipe in use tonight!