Does a North Pole Magnetic Field Create AC in a Wire Passing Through?

[arevolutionist]

I fail to recall this concept. When only a north pole magnetic field is passed along a wire, and then the magnet passes the reversed direction, does the electric current become an AC? The wire never enters the south pole magnetic field.

 

[berkeman]

When the magnetic flux through a wire *loop* changes, that induces a voltage between the ends of the loop. If the flux is changing at a constant rate (like increasing linearly), the coil voltage is DC. If the flux is changing with time (like moving a magnet past a loop, or as in the secondary of a transformer), then the output is AC.

 

[ravenprp]

Yes, the electric current in the wire will become alternating current (AC) when a north pole magnetic field passes through the wire and then the magnet passes in the reversed direction. This is because the changing magnetic field induces a changing electric field in the wire, which in turn causes the electrons in the wire to move back and forth, creating an alternating current. The wire does not need to enter the south pole magnetic field for this to occur. This concept is known as electromagnetic induction.