# Capacitor with two dielectrics.

## Homework Statement

A parallel-plate capacitor contains two dielectrics of different electric permitivities and conductivities 1 and 2, respectively (they are separated by a line with the horizontal). A voltage V is applied to the terminals, find:
The free and polarization charge densities.
The resistance and capacity, in terms of the given parameters.

## The Attempt at a Solution

Not sure how to answer the first question, I think they should be zero but I'm not sure why. I can see why the free charge density is zero in a dielectric (no free motion of electrons) but not polarization density (when a voltage is applied dielectric will become polarized).

For resistance I'd just use ohm's law and rewrite I as the flux integral JdS, and rewrite J in terms of the conductivity and electric field, but should I add the two conductivities?

Same goes for the capacity, I could just use the expression for a parallel plate capacitor, but I'm not sure if I'd need to add both permitivities or do something else.

## Answers and Replies

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