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Electric field inside solenoid

  1. Aug 24, 2014 #1


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    I am trying to find out the electric field inside a solenoid if a time varying current is passed through.
    However I am stuck with these partial differential equations.
    View attachment Electric field solenoid.pdf
    Somehow I can't solve them and I think something is wrong.
    Because according to equation (13) the electric field will vary with frequency sigma/epsilon.
    However when looking at equation (11) the electric field must be varying with the frequency of the magnetic field, which is arbitrary.
    I am really confused.
    Does anybody know the answer?

    Last edited: Aug 24, 2014
  2. jcsd
  3. Aug 25, 2014 #2
    Your picture doesn't appear, if you check the picture you uploaded is there than I can be sure to help out
  4. Aug 25, 2014 #3


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    there is no pic ... it's a link to a PDF file to open and it works OK :)

  5. Aug 30, 2014 #4


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    So does nobody have an answer to my question?
  6. Aug 31, 2014 #5

    Since you have a time varying current, the electromagnetic field created by the solenoid varies with time. The electromagnetic 'news' travels at the speed of light though. You use the quasi-static approximation
  7. Aug 31, 2014 #6


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    If the solenoid is wound with a perfect conductor, and in free space,
    then the ratio of the electric field to the magnetic field will be the intrinsic impedance of free space.
    Zfs= 4*10-7 * Pi * c = 376.73 ohm
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