Voltages in an induced current

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Discussion Overview

The discussion revolves around the relationship between voltage, induced current, and magnetic flux in the context of a solenoid. Participants explore how Faraday's and Ampère's laws apply to the situation, particularly focusing on the visualization of voltage in a circular path within the solenoid.

Discussion Character

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

Main Points Raised

  • One participant expresses confusion about how voltage relates to induced current in a solenoid, questioning the implications of constant magnetic flux along a circular path.
  • Another participant clarifies that voltage represents the difference in electric potential energy between two points, suggesting that current flows due to potential differences.
  • A later reply questions whether Faraday's law applies in this scenario, indicating a lack of clarity about the relationship between voltage and induced current.
  • Some participants affirm that Faraday's law does apply, emphasizing the role of changing magnetic fields in generating electric fields and the subsequent motion of charge carriers due to the Lorentz force.
  • One participant reflects on their understanding of voltage visualization in the coil, indicating a realization about the Lorentz force's role in this context.

Areas of Agreement / Disagreement

Participants generally agree that Faraday's law applies to the situation, but there remains uncertainty about the visualization of voltage and its implications for induced current. Multiple viewpoints exist regarding the interpretation of voltage in this context.

Contextual Notes

Participants express varying levels of understanding about the application of Faraday's law and the Lorentz force, indicating potential gaps in assumptions or definitions related to voltage and induced current.

Mzzed
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I've been messing around with ampere's and faraday's laws as we have recently been applying them in undergrad level physics. I'm confused as to how voltage fits in with these laws when used for a solenoid inducing a current in a material placed inside the solenoid. I know that the induced current will flow in a circular motion and the voltage is determined by change in magnetic flux over time. But at a specific radius that the current is flowing around within the solenoid, there should be a constant amount of changing flux along the perimeter of the same radius. So there is obviously something I am missing, but to me this would mean there is constant voltage along the circular path that the current flows which makes no sense to me since the current would usually flow from high to low voltage.

How can voltage be easily visualized in this situation? Or have I assumed anything incorrectly?
 
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Welcome to PF;
The voltage is the difference in electric potential energy between two points.
Current naturally flows between points where there is a non-zero potential difference.
But that is not the only way to move charges about.

Just like masses naturally roll down between places where there is a gravitational potential difference ... but that is not the only way to move masses around.
 
Simon Bridge said:
Welcome to PF;
The voltage is the difference in electric potential energy between two points.
Current naturally flows between points where there is a non-zero potential difference.
But that is not the only way to move charges about.

Just like masses naturally roll down between places where there is a gravitational potential difference ... but that is not the only way to move masses around.
Hmmmmm ok so does that then mean lens's/faraday's law (V = - change in flux / change in time) does not apply to this situation? if anything I now have more questions than I started with haha
 
It certainly does apply !
Mzzed said:
I now have more questions than I started with
Good condition for learning opportunities :smile:. Work out such questions a bit and post when stuck !

The underlying equation is one of the maxwell equations: a changing magnetic field causes an electric field. Then the motion of charge carriers follows from the Lorentz force, equally fundamental.
 
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BvU said:
It certainly does apply !
Good condition for learning opportunities :smile:. Work out such questions a bit and post when stuck !

The underlying equation is one of the maxwell equations: a changing magnetic field causes an electric field. Then the motion of charge carriers follows from the Lorentz force, equally fundamental.
AHH ok I think the thing I was missing is the lorentz force to enable a better visualisation of voltage in the coil, I think from this i can figure out roughly what a graph of voltage over the cross section of the coil would look like I hope. Thankyou!
 

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