Leakage resistance in a capacitor

[Dan_tanner]

Homework Statement

I am trying to find the relevant equation to to solve the following problem,

RL= leakage resistance measured across the dielectric

A 100pF parallel-plate capacitor has a mica dielectric of relative permittivity \epsilon[/r]=12 and a resistivity of \rho=10^14\Omega m. <br /> <br /> I want to calaculate the leakage resistance of this capacitor.<br /> <br /> <br /> <h2>Homework Equations</h2><br /> <br /> <br /> <br /> <h2>The Attempt at a Solution</h2><br /> <br /> The previous question wanted to know the area and distance between the plates of the capacitor, i think that this has something to do with the answer to the question,<br /> <br /> I have solved this!<br /> <br /> I think i have all the relevant information to have an atempt at the answer but don&#039;t know and can&#039;t find the equation, <br /> <br /> I am not sure if Resistance R = rhol/A has anything to do with it because it states resistivity is \rho = 10^14 \Omega m<br /> <br /> this has thrown me??<br /> <br /> I can&#039;t find anything that points me in the right dierction in my books or course work.

 

[Defennder]

You're missing a needed formula here which gives you the capacitance of an ideal parallel plate capacitance. Use that and your resistance formula to find R.

 

[Dan_tanner]

Hello Defender,

Thanks for the reply, I am still not sure, i don't really understand what you are on about? I am all mechanical ad never had to do electrical before.

Are you on about C= epsilon r epsilon o * A / d

If so, this is the formula for finding C which is in farads which i have already been given as100pF

 

[Defennder]

You can transpose the formula to to obtain an expression to help you calculate resistance from the other formula.

 

[Kev1n]

Hello Defender,

Thanks for the reply, I am still not sure, i don't really understand what you are on about? I am all mechanical ad never had to do electrical before.

Are you on about C= epsilon r epsilon o * A / d

If so, this is the formula for finding C which is in farads which i have already been given as100pF

Dan,

Did you ever get the formula as I am stuck on asimilar question