A resistor of resistance 30 Ω and a capacitor of capacitance \( (250\,\pi^{-1})\,\mu\mathrm{F} \) are connected in series to a 220 V, 50 Hz source. The current in the circuit is
Answer & explanation
Correct answer: option 3
The correct answer is Option (3) → 4.4 A
In a series RC circuit the current is the rms voltage divided by the impedance \( Z = \sqrt{R^{2} + X_C^{2}} \).
\( \displaystyle X_C = \frac{1}{2\pi f C} = \frac{1}{2\pi \times 50 \times \frac{250}{\pi}\times10^{-6}} = \frac{1}{0.025} = 40\,\Omega \)
\( \displaystyle Z = \sqrt{30^{2} + 40^{2}} = 50\,\Omega \)
\( \displaystyle I = \frac{V}{Z} = \frac{220\,\mathrm{V}}{50\,\Omega} = 4.4\,\mathrm{A} \)
Note: NTA picked this question from an NCERT (2026-27) example and changed the figures. Do not ignore NCERT while practising numericals.
NCERT (2026-27):
Resonance – …
