Direction of flow of the electrons

AI Thread Summary
Moving a magnet among a conductor in a closed circular loop generates an electromotive force (EMF) that causes electrons to flow in a specific direction, determined by the orientation of the magnetic field relative to the movement. The direction of electron flow can be analyzed by switching reference frames, treating the conductor as moving instead of the magnet. The force on the electrons can be calculated using the equation F = qv × B, where v is the velocity of the electrons and B is the magnetic field. Additionally, the winding direction of the coil affects the polarity of the output; reversing the winding changes the positive and negative outputs. Understanding these principles is crucial for applications involving electromagnetic induction.
stmartin
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Look at this http://img130.imageshack.us/img130/2954/untitled42dg5.jpg"
What will happen if I move magnet among conductor in closed circular loop, so the magnetic field lines will be in opposite direction of the movement of the magnet? In which direction the electrons will flow and WHY?
 
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stmartin said:
Look at this picture.

A "please" would be nice.
 
Explain why it is like that, like on the site you gave me please.
 
One way you can figure out how the electrons in the conductor move is by going to a different reference frame where it is the conductor that is moving and not the magnet. If in the original frame the magnet moved with velocity v. In the new frame the magnet is stationary and the electrons of the conductor are moving with velocity -v. Thus you can just use
<br /> \vec F = q\vec v \times \vec B<br />
to find the force on the electrons and figure out their subsequent motion.
 
Of course you can also reverse the way the coil is wired and that will reverse the positive and negative output. There is a right and left way to wind coils, neither are the only correct way, its just winding it one way as the magnet approaches gives positive and negative one way and winding the coil the other way gives the opposite polarity output, assuming I am not mistaken here. I have wound coils and powered them with batteries using a compass to measure the north and south on the coils openings. And kept the polarity the same but wound the coil the opposite way and got a different north and south polarity at the same opening. So I am assuming here this works the same way with a magnet approaching a coil, its all according to which direction, left or right,, that the coil is wound,, gives you your polarity or magnetic field.
 
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