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The capacitance of a capacitor depends on the dielectric constant (relative permittivity) between the plates. The maximum charge that can be stored on a capacitor depends on the maximum potential difference across the plates of the capacitor which in turn depends on the maximum electric field (breakdown potential gradient - dielectric strength) which the ...


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You use the metric of your coordinate system; if that's Cartesian, then it's a Kronecker delta. Since permitivity is measured in Farads per meter- emphasis "per meter"-- it should transform accordingly.


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I think the answer is clearer if you consider the equipotential as shown in the diagram below. Forgive their straight line nature as they were easier to draw that way. Given that $\vec E$ must be perpendicular to an equipotential surface then in your computation of potential difference $\displaystyle V_{AB}=-\int_B^A\vec{E\,}\cdot\mathrm d\vec{r\,}$ the ...


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Assume that the voltage across an isolated capacitor with air ($\approx$ vacuum) between the plates of separation $d$ is $V_{\text{air}}$ and the charge stored on the capacitor is $Q$. $Q = C_{\text{air}} V_{\text{air}}$ The electric field between the plates is $E_{\text{air}} = \dfrac {V_{\text{air}}} {d} $. Now put a dielectric of relative ...


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Dielectric implies nonmagnetic, so the best example of an insulator that isn't a dielectric I can think of is ferrite crystals like yttrium iron garnet, that show a magnetic response while having low or zero conductivity. There are also ferroelectric materials that show a permanent polarization in response to an electric field, and these aren't considered ...


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In my understanding, the free charge is any charged particle that is not being restrained in the boundary, while the bound charge is in the boundary.It does not matter whether the material you currently discuss is a dielectric or a conductor.


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Boundary conditions of electromagnetic waves are well looked into because of the nature between polarization and reflection. However in this particular case it is rather simple, it is the evaluation of a contour integral over the boundary. This is done by summing the length elements of the pill-box shape that is typically used in this analysis in the correct ...



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