What makes the electrons move in conductor? (em induction)

AI Thread Summary
The movement of electrons in a conductor is induced by the electric field created by a changing magnetic field, as described by Faraday's law of induction. When a magnet is moved towards a closed loop, it increases the magnetic flux, prompting electrons to move in a direction that opposes this increase, in accordance with Lenz's law. This opposition is a manifestation of the conservation of energy, as energy is required to maintain the current flow against the induced forces. When the magnet is pulled away, the electrons move to increase the flux, again requiring energy to counteract the change. Understanding these principles clarifies the relationship between magnetic fields and electric currents in conductors.
Physicsissuef
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What makes the electrons move in conductor, while I am moving the magnet among the conductor in closed circular loop? It is the magnetic force from the magnet, but why when I get close the magnet they start moving in direction, oppose of the magnetic force?
 
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What moves the electons is the induced electric field created by the moving magnetic field. The current is always induced in a direction to oppose any change in the magnetic flux through the loop. As you move the pole of a magnet towards the loop, you are increasing the flux in the loop--the electrons will move to reduce it.

See: http://hyperphysics.phy-astr.gsu.edu/hbase/electric/farlaw.html"
 
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Doc Al said:
What moves the electons is the induced electric field created by the moving magnetic field. The current is always induced in a direction to oppose any change in the magnetic flux through the loop. As you move the pole of a magnet towards the loop, you are increasing the flux in the loop--the electrons will move to reduce it.

See: http://hyperphysics.phy-astr.gsu.edu/hbase/electric/farlaw.html"

Why they want to reduce it?
 
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It's a consequence of the conservation of energy. Read those links.
 
This question made me think. Do only electrons produce an electric field, and what would the electric field be composed of? I am assuming the electric field is continuous with no gaps. I don't think it's solid electrons. I guess it's just some form of energy.
 
nanoWatt said:
This question made me think. Do only electrons produce an electric field, and what would the electric field be composed of? I am assuming the electric field is continuous with no gaps. I don't think it's solid electrons. I guess it's just some form of energy.

Er.. this may be rather obvious, but protons do have charges too, you know.

And a changing magnetic field also produces electric field, per the Maxwell equations.

Zz.
 
Doc Al said:
It's a consequence of the conservation of energy. Read those links.

I read them, but still can't understand. Conservation of energy of the electrons or?
 
Doc Al?
 
Physicsissuef said:
Conservation of energy of the electrons or?
It takes energy to get a current flowing. That energy comes from the work you have to do in pushing the magnet into the loop. (The induced current exerts a force on the magnet that opposes its motion--you have to push the magnet, which takes energy.)
 
  • #10
Doc Al said:
It takes energy to get a current flowing. That energy comes from the work you have to do in pushing the magnet into the loop. (The induced current exerts a force on the magnet that opposes its motion--you have to push the magnet, which takes energy.)
And when I push the magnet back, why the electrons are going in same direction of the magnetic field, so they want to connect with it?
 
  • #11
Physicsissuef said:
And when I push the magnet back, why the electrons are going in same direction of the magnetic field, so they want to connect with it?
The induced current always resists any change in flux. When you pull the magnet back you are acting to decrease the flux, so the current moves so as to increase it. (Again, this takes energy. You have to pull the magnet.)
 
  • #12
Doc Al said:
The induced current always resists any change in flux. When you pull the magnet back you are acting to decrease the flux, so the current moves so as to increase it. (Again, this takes energy. You have to pull the magnet.)
Ok, I understand that. But why it wants to increase it?
 
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