<p>(a) When a series LCR-circuit is brought into resonance, the current in the circuit increases to a large value. Why ?</p>

<p>(b)&nbsp;An air core coil and an electric bulb are connected in series across a 220 V, 50 Hz a.c. source. The bulb glows with some brightness. How will the glow of the bulb be affected on introducing a capacitor in series in circuit ? Justify your answer.</p>