
148 Network Analysis and Synthesis
The inductive reactance (X
L
) causes the total current to lag the source voltage. The capacitive
reactance (X
C
) has the opposite effect. It causes the total current to lead, lag, or be phase with
the voltage source. Thus, X
L
and X
C
will tend to cancel each other’s effect. In case X
L
equals X
C
at a particular frequency, they will cancel each other and the total impedance of the circuit will
be the resistance only. With the supply voltage of variable frequency, at a particular frequency,
X
L
will be equal to X
C
. Such a condition is called resonance. It is interesting and of practical
importance to study the effect ...