Does the Skin Effect cause charge to accumulate on the surface of a conductor?

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Discussion Overview

The discussion centers around the skin effect in conductors and its relationship to charge accumulation on the surface of a conductor. Participants explore how to maximize surface charge and the implications of using different current types, particularly in the context of high-frequency applications.

Discussion Character

  • Exploratory
  • Technical explanation
  • Debate/contested

Main Points Raised

  • One participant inquires about methods to achieve maximum charge accumulation on the surface of a conductor, referencing the skin effect and eddy currents.
  • Another participant suggests that to maximize surface charge, the conductor should be charged relative to its environment or earth, emphasizing the importance of high voltage.
  • Some participants argue that the skin effect is unrelated to surface charge and primarily affects resistance due to surface currents in rapidly changing conditions.
  • There is a discussion about using specific geometries, such as coaxial cables, to achieve a desired distribution of surface charge.
  • One participant expresses confusion about the relationship between electric current and charge accumulation, noting the need for surface currents at high frequencies.
  • Another participant points out that any alternating surface current would inherently transmit electromagnetic waves, regardless of the intent to avoid transmission.
  • Suggestions are made regarding the construction of the conductor, including using thin metal sheets or depositing conductive films on insulators.
  • Participants discuss the implications of using scrap metal as a conductor and the challenges in controlling current flow to the surface.

Areas of Agreement / Disagreement

Participants express differing views on the relationship between the skin effect and surface charge accumulation. While some agree on the need for high voltage to maximize surface charge, others contest the relevance of the skin effect to the original inquiry. The discussion remains unresolved with multiple competing perspectives.

Contextual Notes

Participants mention various assumptions regarding the geometry of the conductor and the nature of the currents involved. There are unresolved questions about the specific parameters required for achieving the desired surface current behavior.

  • #31
Sibilo said:
the current follows the path with less resistance
A point of information; this is not true. Current is shared between multiple paths and the proportion of each share. relates to the resistance (the inverse of the resistance) of each path. This is very relevant to how anything you build will perform.
Sibilo said:
I really don't need an image or photo in my opinion,
You certainly do need one if you want to make any sense to us. I would go as far as to say that. if you can't draw your plan then you could never build your experiment.
 
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  • #32
Baluncore said:
Such as liquid mercury or molten metal?

Which water surface with what? Across the boundary between the conductor and the electrolyte?
Or along the conductor surface, parallel to and within the conductor, but not along the electrolyte boundary equipotential contact with the conductor?

The conductive electrodes must be in contact with the electrolyte for an electron or ionic current to flow. If you place conductive electrodes on the surface of an electrolyte solution, an ionic current will flow deep through the volume of the solution. Ions move both ways through the liquid electrolyte, while electrons move through the conductive metal electrode. The ionic current flows through the bulk of the liquid, not along its external surface.

It is only where the electron current that flows in the conductor, is converted to an ionic current flowing in the electrolyte, that electrochemical reactions take place between the conductor and the electrolyte.

The EM skin effect is only significant in materials that make excellent electrical conductors.
Yes, you said it right, in fact in electrolytes we are talking not about electronic conduction but about the migration of ions. Furthermore, I didn't know that the skin effect doesn't work in electrolytes and therefore there is no conduction on the surface, this puts me in difficulty. I have to place the conductive electrodes in contact with the surface of the electrolyte liquid, without going deep but just touching it. furthermore I cannot use a DC because in this case I would start a chemical reaction, electrolysis. so now considering the question of electrolytes, how can I make the current flow on the surface? or more generally, how can I make the current spread as much as possible throughout the entire volume of the electrolyte, therefore also in depth?
 
  • #33
Sibilo said:
... how can I make the current flow on the surface?
Use a thin sheet of electrolyte, maybe between two glass plates, with electrodes at opposite edges between the plates.

How can you have an AC or DC current flow, without a chemical reaction at the electrode-electrolyte contact ?

You are wasting our time by not explaining what you are actually trying to achieve.
 
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  • #34
Baluncore said:
You are wasting our time by not explaining what you are actually trying to achieve.
Yeah, agreed. OP is now on a short leash in this thread...
 
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  • #35
Baluncore said:
Use a thin sheet of electrolyte, maybe between two glass plates, with electrodes at opposite edges between the plates.

How can you have an AC or DC current flow, without a chemical reaction at the electrode-electrolyte contact ?

You are wasting our time by not explaining what you are actually trying to achieve.
ok gentlemen I will do some tests for each object I use. no but I'm not wasting your time, as I already said, these are small experiments that I want to do out of curiosity, so maybe I'll do some tests and see what happens.
 
  • #36
berkeman said:
Yeah, agreed. OP is now on a short leash in this thread...
no Berkemann I'm not in a corner, but I've already said that I want to do some tests with many different conductive objects, so I'll start doing the tests
 
  • #37
It's a bit lenghty to do it here in the forum, but why don't you just try to solve Maxwell's equations for the field given an (infinitely long for simplicity) conducting cylindrical wire? You find a thorough discussion in A. Sommerfeld, Lectures on theoretical physics, vol. 3.
 
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