0
$\begingroup$

I have been trying to find out how using different conductive materials for each parallel plate for a parallel plate capacitor will effect the field strength.

Meaning if one of the parallel plates has a surface resistance of say $0.01\ \Omega^2$ and the other parallel plate is $100\ \Omega^2$, how does this effect the strength of the electric field against parallel plates that have a balanced surface resistance of say $1\ \Omega^2$?

What I am trying to understand is if the field strength is more of an averaging between the surface resistance two materials or if the field strength is determined by one or other of the two different materials.

I would add that this is a fairly new area for me and I would appreciate more of a layman's explanation rather than a very technical one.

$\endgroup$
1
$\begingroup$

If you are considering a fixed charge on the capacitor, it won't matter at all. The charges have plenty of time to distribute themselves evenly over the plates, so there is no current anywhere, so no voltage drop.

If you are considering conditions during the charge cycle, the charges in the low resistance plate will spread out more quickly. If the leads attach to the center of a circular plate, the charges won't get to the edge of the high resistance plate, so the field lines will only cover the inner portion of the high resistance plate while they cover the whole low resistance plate. You should have a time constant of $RC$ with some equivalent $R$. If you charge it up statically and then discharge it dynamically, the charges in the high resistance plate will "get stuck" at the edges a bit.

$\endgroup$

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.