Q 12-07-119JEE MainJEE Main 2021 (18 Mar, Shift 2)Easy
In a series LCR circuit, the inductive reactance $(X_L)$ is $10\ \Omega$ and the capacitive reactance $(X_C)$ is $4\ \Omega$. The resistance $(R)$ in the circuit is $6\ \Omega$. The power factor of the circuit is:
Answer: (C) $\frac{1}{\sqrt2}$
$Z = \sqrt{R^2 + (X_L - X_C)^2} = \sqrt{36 + 36} = 6\sqrt2\ \Omega$, so $\cos\phi = \dfrac{R}{Z} = \dfrac{1}{\sqrt2}$.
Solution by Sreeraj P, M.Sc Physics