
Steady State Analysis of AC Circuits 125
As can be seen from the impedance triangle of Figure 3.35,
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Example 3.15 In an L–R–C series circuit, the voltage drops across the resistor, inductor and
capacitor are 20V, 60 V and 30 V, respectively. Calculate the magnitude of the applied voltage
and the power factor of the circuit.
Solution: In Figure 3.36, the voltage drops across
the circuit components and their phase relationship
have been drawn. Since it is a series circuit, it is
always convenient to have current as the reference
axis. ...