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CassieFordham

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I'm trying to get a better understanding of the relationship of dielectric constant (relative permitivity) to dielectric strength (breakdown voltage).I want to know what happens when you layer materials of high dielectric constant but low dielectric strength with materials of low dielectric constant but high dielectric strength. For example Barium titanate has a dielectric constant of 1200, But a dielectric strength of only 1.2 Mv/m. Mica has a dielectric strength of 118 Mv/m, but a dielectric constant of only 3.

if you put a 1mm sheet of mica between 2 1mm sheets of barium titanate, what would be the combined dielectric constant and dielectric strength?

I came up with 4 possible scenerios:

1. The barium titanate being next to the plates would determine the dielectric constant, with no effect from the mica. Mica having the highest dielectric strength, the combined dielectric strength would be determined the percentage of mica. Thus the combined dielectric strength would be 39.33 MV/m and the combined dielectric constant would be 1200.

2. The dielectric constant would be limited by the mica. Thus the combined dielectric strength would be 39.33 MV/m and the combined dielectric constant would be 3.

3. The dielectric constant and dielectric strength would be would be limited by the lowest common denominator. Thus the combined dielectric strength would be 1.2 MV/m and the combined dielectric constant would be 3.

4. Both materials detrmine the dielectric constant and dielectric strength, which probably could only be determined experimentally.

Are any of these Correct, and if not what is correct and why?