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Potential difference across an inductor

  1. Aug 21, 2013 #1
    I have some confusion about how emf across an inductor is generated:

    The potential difference across an inductor is an induced emf produced by the changing magnetic flux through the coils of the inductor.

    In general, electric potential is a scalar potential of the electric field. Hence the electric field is the gradient field of the electric potential, and is a conservative vector field (for stationary charges at least). Conservative vector fields are irrotational (having zero curl) and irrotational vector fields are conservative (on simply connected domains).

    Now according to Resnick & Halliday, "electric potential has meaning only for electric fields that are produced by static charges; it has no meaning for electric fields that are produced by induction." This is because the electric field induced by a changing magnetic flux is rotational in nature, rather than emanating from a source of charge.

    So if we can't define a potential function for the induced electric field, how can we define potential across an inductor that allows us to solve circuits etc. ?

    Note my knowledge of E&M is rather rudimentary, but am willing to browse through more advanced texts to get a better understanding.

    BiP
     
  2. jcsd
  3. Aug 21, 2013 #2
    check Feynman lectures on physics, part II chapter on AC circuits beginning from 22-1. I think it is what your are looking for. I think Feynman explains it better than I would.
     
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