What Is the Electric Field Inside a Solenoid with Time-Varying Current?

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The discussion revolves around determining the electric field inside a solenoid with a time-varying current. The original poster is confused by the relationship between the electric field's frequency and the magnetic field's frequency, as outlined in their equations. A participant clarifies that the electromagnetic field from the solenoid varies with time and that the quasi-static approximation can be applied. They also mention that if the solenoid is made of a perfect conductor, the ratio of the electric field to the magnetic field is equal to the intrinsic impedance of free space. The conversation highlights the complexities of solving the relevant partial differential equations in this context.
VVS
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Hello,

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?

thanks
VVS
 
Last edited:
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Your picture doesn't appear, if you check the picture you uploaded is there than I can be sure to help out
 
SteliosVas said:
Your picture doesn't appear, if you check the picture you uploaded is there than I can be sure to help out

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


Dave
 
So does nobody have an answer to my question?
 
VVS said:
So does nobody have an answer to my question?



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
 
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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