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Homework Help: Microscopic Ohm's Law

  1. Apr 16, 2009 #1
    1. The problem statement, all variables and given/known data
    Explain the terms used in the microscopic version of Ohm's Law

    2. Relevant equations

    3. The attempt at a solution
    Well I know what we have here is the current density within a conductor is equal to its conductivity multiplied by an 'E-field'. But what is this E-field? Is it an external field that acts upon the wire? But if this is the case will the electrons in the conductor not just move in a few microseconds to go back into equilibrium meaning j=0. You could act on it with an varying field but then how would the calculation work out?
    Or is E the field inside the conductor caused by the current density?
  2. jcsd
  3. Apr 16, 2009 #2


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    Maybe this helps?
  4. Apr 16, 2009 #3
    Hmmm I guess I've spent so long doing electrostatics that I'm struggling a bit with the intuition of currents.
    So from the link above, am I right in thinking the E field is from within the wire caused by a potential difference from a power source?
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