RL and RC Series Circuits question from NEET 2015 (AIPMT)

Answer: (d)

1. Mica has higher dielectric constant, so $C_b > C_a$ and $X_{C,b} < X_{C,a}$.
2. Current $i = \frac{V_0}{\sqrt{R^2 + X_C^2}}$: smaller $X_C$ gives larger current, so $i_a < i_b$.
3. Capacitor voltage $V = \frac{V_0 X_C}{\sqrt{R^2 + X_C^2}}$ increases with $X_C$, so $V_a > V_b$.
4. So the answer is (d) $V_a > V_b$.