in the figure, there are only 5 of resistance as compared with 200 of inductive reactance and 200 of capacitive

reactance. To find impedance, use vector notation.

Since the reactances are equal and opposite, they cancel out and the only opposition in the circuit is the resistance. The

impedance of a series resonant circuit is, therefore, only the resistance in the circuit. To find the current do the

following.

(IT means total current.)

Note that the current of a series resonant circuit is in phase with the applied voltage. The power factor of the circuit is

one.

A more interesting fact about the series resonant circuit is concerning the magnitude of the voltage across the coil and

capacitor. The voltage across the coil (inductance) is

EL = IXL = (2) X (200) = 400 V.

The voltage across the capacitor is

EC = IXC = (2) X (200) = 400 V..

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