Answer:
Option B
Explanation:
Given R= XL = 2XC
Z = $\sqrt{R^{2} + (X_{L}-X_{C})^2}$
= $\sqrt{(2X_{C})^2 + (2X_{C}-X_{C})^2}$
= $\sqrt{4X_C^2+X_C^2}$
= $\sqrt{5X_{c}}$ = $\frac{\sqrt{5R}}{2}$
['.'R = 2XC]
$\tan\phi = \frac{X_{L} - X_{C}}{R}$
= $\frac{2X_{C} - X_{C}}{2X_{C}}$
$\tan\phi = \frac{1}{2}$ ; $\phi = \tan^{-1}(\frac{1}{2})$