Power factor in LCR circuit is given by,
cosϕ=ZR, where, Z is the total impedance of the circuit.
So, cosϕ=R2+(XC−XL)2R
Putting the values, we have
⇒cosϕ=(80)2+(60)280
⇒cosϕ=10080⇒108
Thus, the value of x=8.
JEE Main 2023 — Physics Electromagnetism
A series LCR circuit is connected to an AC source of 220V, 50Hz. The circuit contains a resistance R=80Ω, an inductor of inductive reactance XL=70Ω, and a capacitor of capacitive reactance XC=130Ω. The power factor of circuit is 10x. The value of x is:
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