In a DC circuit, there is

no currentthrough a capacitor -- or through this simple circuit that contains a capacitor.In a simple resistor circuit, we defined resistance R by

V = I R In a similar fashion, we can write

V _{C}= I X_{C}where V

_{C}is the maximum voltage across the capacitor and I is the maximum current through the circuit. X_{C}is called the "capacitive reactance"; it is analogous to resistance and is also measured in ohms (). The "capacitive reactance", X_{C}, is given by## X

_{C}, the "Capacitive Reactance" plays a role very similar to that of R, the resistance. The capacitive reactance is a measure of how difficult it is for current to flow. With AC circuits, this depends upon the frequency.(c) Doug Davis, 2002; all rights reserved

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