XL=31Ω,XC=25Ω,R=8Ω ∴ impedance of series LCR is Z=R2+(XL−XC)2=82+(31−25)2=64+36=100=10Ω Power factor cosϕ=2R=108=0.8
NEET UG 2006 — Physics Electromagnetism
A coil of inductive reactance 31Ω has a resistance of 8Ω. It is placed in series with a condenser of capacitative reactance 25Ω. The combination is connected to an a.c. source of 110 V. The power factor of the circuit is:
Held on 30 Apr 2006 · Verified 9 Jul 2026.
0.33
0.56
0.64
0.80
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