How does current behave in response to changes in magnetic field?

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Discussion Overview

The discussion revolves around the behavior of electric current in response to changes in a magnetic field, specifically in the context of Lenz's law. Participants explore the implications of magnetic pole movement on electron flow and induced current, addressing both theoretical and conceptual aspects.

Discussion Character

  • Exploratory
  • Technical explanation
  • Conceptual clarification
  • Debate/contested

Main Points Raised

  • Some participants reference Lenz's law to explain how the induced current opposes changes in the magnetic field.
  • There is a discussion about the direction of electron flow versus conventional current, with some clarifying that electrons move opposite to the direction of conventional current.
  • One participant questions the reasoning behind the behavior of electrons when the magnetic field is increasing or decreasing, seeking clarification on the relationship between magnetic pole movement and electron response.
  • Another participant emphasizes that the current opposes changes in the magnetic field, suggesting that if the magnetic field decreases, the induced current must act to increase it.
  • There is a repeated inquiry about the nature of forces acting on electrons in relation to the approaching and receding magnetic poles.

Areas of Agreement / Disagreement

Participants express differing views on the specifics of electron behavior and the implications of Lenz's law. There is no consensus on the underlying reasons for the observed phenomena, and the discussion remains unresolved.

Contextual Notes

Participants have not fully resolved the assumptions regarding the definitions of current and electron flow, nor have they clarified the conditions under which the magnetic field changes are analyzed.

stmartin
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http://hyperphysics.phy-astr.gsu.edu/hbase/electric/farlaw.html#c2
Why, first, when the magnetic field is approaching with the N pole, the electrons are opposing on the increase of the field? Why when N is receding, the electrons are going into direction of the move of the magnet?
 
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It's experimentally seen -- Lenz's law.
 
you can have a feel if u draw lines.When n pole is approaching the electrons will face a force that will take them away from it and vice versa.
Hope it helps!
 
premagg said:
you can have a feel if u draw lines.When n pole is approaching the electrons will face a force that will take them away from it and vice versa.
Hope it helps!
what force? attractive or repulsive?
 
I won;t tell u to mug it up.Just calculate from the frmula q(v*B)
 
stmartin said:
http://hyperphysics.phy-astr.gsu.edu/hbase/electric/farlaw.html#c2
Why, first, when the magnetic field is approaching with the N pole, the electrons are opposing on the increase of the field? Why when N is receding, the electrons are going into direction of the move of the magnet?
What do you mean by "the electrons are going into direction of the move of the magnet"? Do you mean that the electrons are going from left to right, the same direction that the magnet is moving? If so, realize that the arrow refers to conventional current, not electron flow (electrons move in the opposite direction). Also realize that the sideways movement of the current depends on how the coil is wound.

You've asked similar questions many times, so I don't know what kind of answer you are looking for when you ask "why" this happens. Is there something special about when the N pole is receding that puzzles you? Or do you have the same question about all four examples on that page?

Note that in all cases the induced magnetic field acts so as to resist any change in the magnetic field within the coil. (This is Lenz's law.) When the N pole is pulled away from the coil that implies a decreasing field towards the coil--thus the induced magnetic field must act to increase the field in the coil. To create such a field, the induced current must travel as indicated in the coil.
 
Doc Al said:
What do you mean by "the electrons are going into direction of the move of the magnet"? Do you mean that the electrons are going from left to right, the same direction that the magnet is moving? If so, realize that the arrow refers to conventional current, not electron flow (electrons move in the opposite direction). Also realize that the sideways movement of the current depends on how the coil is wound.

You've asked similar questions many times, so I don't know what kind of answer you are looking for when you ask "why" this happens. Is there something special about when the N pole is receding that puzzles you? Or do you have the same question about all four examples on that page?

Note that in all cases the induced magnetic field acts so as to resist any change in the magnetic field within the coil. (This is Lenz's law.) When the N pole is pulled away from the coil that implies a decreasing field towards the coil--thus the induced magnetic field must act to increase the field in the coil. To create such a field, the induced current must travel as indicated in the coil.
But if on the first example, it opposes the increasing of the field, how then when the magnet is going back the field is decreased?
 
stmartin said:
But if on the first example, it opposes the increasing of the field, how then when the magnet is going back the field is decreased?

the current opposes the change in field. so if the field is high and it decreases then current opposes this change by creating more field and vice versa.
 

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