The impedance of the LCR series circuit is given by Z=R2+(XC−XL)2.
Substituting the given values:
Z=802+(80−20)2
Z=802+602
Z=6400+3600=10000=100Ω
The power factor of the circuit is given by cosϕ=ZR.
cosϕ=10080=0.8
Answer: 0.8
JEE Main 2026 — Physics Electromagnetism
A LCR series circuit driven with Erms=90 V at frequency fd=30 Hz has resistance R=80Ω, an inductance with inductive reactance XL=20.0Ω and capacitance with capacitive reactance XC=80.0Ω. The power factor of the circuit is _______.
Held on 6 Apr 2026 · Verified 6 Jul 2026.
0.8
0.64
0.9
0.5
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