A LCR series circuit driven with Erms=90 V at frequency fd=30 Hz has resistance R=80 , an inductance with inductive reactance XL=20.0 and capacitance with capacitive reactance XC=80.0 . The power factor of the circuit is .
(1) 0.8
Z= R2+(XC-XL)2= 802+(80-20)2
= 6400+3600=100
∴ Power factor = = RZ= 80100=0.8
(Erms and fd are not needed.)
Answer: (1)
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