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To remove the apparent inconsistency, we need to revise our notion of what constitutes a current. We generally believe that current being a flow of charge must be the same at all cross sections of a series circuit. This is obviously not true for circuits containing capacitors. Consider an RC circuit. When the switch S is closed, the capacitor charges and the current is given by |
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This does not hold inside the capacitor as the dielectric between the plates is a dielectric (could be air) and does not conduct electricity. In order to preserve the continuity of current inside the dielectric, we need to reconcile the apparent inconsistency. Since the current through the wire  is the rate of flow of charge through the wires, we may express it in terms of the electric field inside the capacitor plates. Since the electric field inside the capacitor is given by  , an equivalent expression for current is |
![\includegraphics[width=\textwidth]{fig3.54.eps}](img/img729.png)
![\begin{displaymath}i = \frac{V}{R}\left[1- \exp(-t/RC)\right]\end{displaymath}](img/img601.png){kind=small}
