Power factor (old) =R2+XL2R=R2+(2R)2R=5RR Power factor (new) =R2+(XL−XC)2R=R2+(2R−R)2R =2RR ∴ Old power factor New power factor =5RR2RR=25
JEE Main 2013 — Physics Electromagnetism
A series LR circuit is connected to an ac source of frequency ω and the inductive reactance is equal to 2R. A capacitance of capacitive reactance equal to R is added in series with L and R. The ratio of the new power factor to the old one is :
Held on 25 Apr 2013 · Verified 6 Jul 2026.
32
52
23
25
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