- #71

Delta2

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I don't think they vanish if we have a RLC circuit in which we apply a very high frequency voltage source such that the wavelength ##\lambda=\frac{c}{f}## (##f## the frequency of the source) is comparable to the distance between the capacitor's C plates. The reason (I think) is that the current and the electric field inside the circuit's wires(and inside the capacitor) become function of position and not only time(e.g the electric field inside the capacitor i believe it would be given by an equation like $$E(x,t)=E_0\sin(2\pi ft+2\pi\frac{x}{\lambda})$$ in the high frequency case) and not just as $$E(t)=E_0\sin(2\pi ft)$$ which is the equation we use in the quasi static approximation.feynman1 said:By dynamic, do you mean AC circuits or LRC ones? Even in these, they still vanish.

So because the electric field will be different inside the two plates, the whole reasoning with Gauss's law that $$\oint_S\vec{E}\cdot d\vec{S}=0$$ falls apart.

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