Help with understanding electromagnetic induction

[coreluccio]

When a charge is in motion, it produces a magnetic field. If the charge is in an external magnetic field, a magnetic force is induced on the charge. This I understand.

When a conductor is moving relative to a magnetic field, there is an induced current in the conductor. This I don't get. If the conductor is stationary, and the magnet is moved around it, then how is there a magnetic force exerted on the electrons in the conductor to induce a current? Wouldn't the conductor need its own magnetic field for a magnetic force to be exerted on it, and for it to have a magnetic field wouldn't it have to be in motion?

Thanks in advance.

 

[hikaru1221]

It doesn't have to be magnetic force to induce current. If the magnet is moved, the field it creates is no longer a static magnetic field; it's electromagnetic field instead. The E-component of the field exerts forces on the electrons of the conductor.

 

[coreluccio]

I don't get it.

 

[hikaru1221]

I don't get it.

Where do you not get it?

 

[coreluccio]

The entirety of what you said.

 

[hikaru1221]

Have a look at this:
http://en.wikipedia.org/wiki/Faraday's_law_of_induction#The_Maxwell-Faraday_equation

 

[Bob S]

Take a look at the illustration of an aviation ignition magneto on page 3 of this article by Will Fox:

http://eaa691.org/files/Tech%20Note%20%232%20Magnetos.pdf

The rotating 4-pole magnet induces an alternating magnetic field in the iron core, which generates a voltage and current in the coil (primary = 180 turns). This is a battery-less ignition system, where the power is generated by the rotating permanent magnet. This works on the Faraday law of induction.

Bob S