Does a solenoid's magnetic flux change when a magnet's pole is moved away?

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Discussion Overview

The discussion revolves around the behavior of magnetic flux in a solenoid when a magnet's pole is moved away. Participants explore the implications of having a permanent magnet attached to one end of the solenoid while another magnet is moved near it, focusing on concepts of magnetic flux, induction, and the role of magnetic poles.

Discussion Character

  • Exploratory, Technical explanation, Debate/contested

Main Points Raised

  • One participant questions whether the solenoid core has magnetic flux from the attached S pole when the N pole of another magnet is not nearby, suggesting that flux may only enter materials with low reluctance when an opposite pole is present.
  • Another participant asserts that the solenoid will indeed have magnetic flux from the attached magnet even when the other magnet is far away, as the field lines loop back to the north pole of the magnet.
  • A participant proposes that the presence of the S pole allows field lines to loop through the solenoid core due to its low reluctance compared to air, but questions whether this flux affects the coil on the solenoid.
  • There is uncertainty about whether the attached magnet affects the induction generated by moving the second magnet, with one participant expressing doubt about the extent of this effect.

Areas of Agreement / Disagreement

Participants express differing views on the impact of the attached magnet on the induction process, indicating that the discussion remains unresolved regarding the influence of the permanent magnet on the induction caused by the moving magnet.

Contextual Notes

Participants discuss the concepts of magnetic flux and induction without resolving the specific conditions under which these phenomena occur, leaving some assumptions and dependencies on definitions unaddressed.

Salvador
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Hi, I was wondering about a simple example.take a coil wound on a solenoid, one side of the solenoid core is permanently attached to a permanent magnet S pole, the other end of the solenoid core is not attached to any magnet.
Now I take another magnet turn it with the N pole facing the solenoid and move it near and then again away from the solenoid, I get induced current in the solenoid coil.my question is this, when the other magnet's N pole is not close or near the solenoid core does the solenoid core has magnetic flux in it from the S pole of the magnet that is attached to it's other side , or does flux only enter a certain material (low reluctance in this case) when the b field has an opposite pole to go into ?
 
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Salvador said:
my question is this, when the other magnet's N pole is not close or near the solenoid core does the solenoid core has magnetic flux in it from the S pole of the magnet that is attached to it's other side , or does flux only enter a certain material (low reluctance in this case) when the b field has an opposite pole to go into ?

Yes, the solenoid will have magnetic flux from the attached magnet pole passing through it even when the other magnet is nowhere nearby. These lines will eventually loop back around to the magnets north pole.
 
and the reason for that is probably because even without the other pole being there the field lines loop back to the other pole of the same magnet and they loop through the solenoid core because its reluctance to field is much less than that of air so the flux will always take that path no matter what right?

ok but then i have a question, does the flux being there in the core even without the other pole affect the coil sitting on the solenoid ? I assume no.I think only when the other pole is passed by the other side of the solenoid core only then the coil on it has induction correct?
so just by having one pole constantly attached doesn't ruin or change anything I can still move the other pole near the other side and get the same amount of induction that I would get when passing both poles of both magnets from each side ?
 
Salvador said:
so just by having one pole constantly attached doesn't ruin or change anything I can still move the other pole near the other side and get the same amount of induction that I would get when passing both poles of both magnets from each side ?

That I don't know. You'll certainly still get some amount of induction, but I don't now how having the magnet attached to the solenoid affects the induction generated by moving the 2nd magnet.
 

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