Electricity Without the analogies (need expert varification)

  • Thread starter tim9000
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  • #1
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The topic of how electricity actually flows is one of the worst answered most common questions I've seen. Best answer I've seen was here by Gokul43201:
https://www.physicsforums.com/showthread.php?t=377359&page=3

I also HATE the "shock-wave" analogy


YET I'm still confused, as I know an electric field cannot propagate inside a conductor, I have read that a conductor is like a medium with infinite permittivity. -> I've seen pictures where the conductor's free charges move to set up an apposing electric field (I think) on the surface.

Crux:
So I always thought that a conducting wire was a TM mode TL, but I haven't seen any literature supporting my assumption (from Right hand screw rule), hence I believe it to be wrong.
Am I to conclude that infact the Electric Flux does indeed flow through at least the skin-depth (if AC) of a conductor at near the speed of 'c', because the charges are able to circulate in a loop? (and thus not oppose the E-field)

It seems weird to me that the conductor would go from having what seemed to be infinite permittivity (like an isolated sphere in an E-field), to almost no permittivity, so the E-field sticks inside the conductor and don't leak out, as it often is not a straight line (wires etc).

(or an adoquate distance for high frequencies, in an antenna)


THANKS
 
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Answers and Replies

  • #2
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For anyone curious, I think I may have found half the answer to my question here:
https://www.physicsforums.com/showthread.php?t=154617&page=2
In that-
"Now, what is an EXTREME change in charge flux, is when it tries to cross the surface of the conductor: it simply can't. So all charge that wants to flow "outside" of the conductor is accumulated on its surface! And this in such a way, that the E-field is modified UNTIL it is entirely parallel to the conductor surface (because only then, no charge wants to "flow outside" and hence gets accumulated more at the surface)."


Although I still wouldn't mind hearing a "no" about the wire not being a TM mode TL, from someone who knew.
 
  • #3
jtbell
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I know an electric field cannot propagate inside a conductor,
This is true in electrostatics, but a current-carrying wire is not an electrostatic situation.
 
  • #4
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This is true in electrostatics, but a current-carrying wire is not an electrostatic situation.
Thanks for clearing that up. Is a current carrying wire of a type of mode TL?
 

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