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Electricity Without the analogies (need expert varification)

  1. Jun 30, 2014 #1
    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:

    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.

    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)

    Last edited: Jun 30, 2014
  2. jcsd
  3. Jun 30, 2014 #2
    For anyone curious, I think I may have found half the answer to my question here:
    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.
  4. Jun 30, 2014 #3


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    Staff: Mentor

    This is true in electrostatics, but a current-carrying wire is not an electrostatic situation.
  5. Jun 30, 2014 #4
    Thanks for clearing that up. Is a current carrying wire of a type of mode TL?
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