How does resistance relate to capacitance?

1 Answer
Jul 23, 2015

Resistance doesn't depend upon capacitance. Impedence does.


Resistance is due to intrinsic properties of a substance. It is the restriction the substance imposes on the flow of an electric current through it. It has nothing to do with capacitance.

On the other hand, in case of alternating current circuits, due to the presence of capacitative and inductive elements, and their ability to store electromagnetic energy, they in addition to resistive elements impose a greater restriction to the flow of alternating currents.

The individual opposition is termed as capacitative reactance #X""_c# for a capacitor and inductive reactance #X""_L# for an inductor.

The net restriction imposed is quantitatively given by a quantity, which we term as impedence. The impedence #Z# is given by the mathematical equation,

# Z = [ R^2 + (X""_C^2 - X""_L^2)]^(1/2)#