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a magnet is pushed into the center of a wire loop and then stops. what is the current in the wire loop when the wire stops moving? explain.

Respuesta :

AL2006

-- If the ends of the wire loop are open (not connected to anything)
then there's never any current in it, no matter what you do with the
magnet.

-- If there's some kind of conductor between the ends of the wire
loop, then

-- While you're pushing the magnet, a current is flowing in the wire. 
The current creates a magnetic field around the wire, and some of
the energy you're using to push gets stored in the magnetic field.

-- When you stop pushing and the magnet stops moving, the energy
stored in the magnetic field keeps the current flowing in the wire for
a short time, and then everything stops.

This all happens so fast, and lasts for such a short time, that you'd
never notice it unless you were set up with special equipment to
measure it.