Alternating Current

A coil of inductive reactance $1/\sqrt{3} \mathrm{\Omega }$ and resistance 1 Ω is connected to a 200 V, 50 Hz AC supply. The time lag between maximum voltage and current is

• $\frac{1}{200} \mathrm{s}$

• $\frac{1}{300} \mathrm{s}$

• $\frac{1}{500} \mathrm{s}$

• $\frac{1}{600} \mathrm{s}$

In the A.C. circuit shown, keeping 'K' pressed, if an iron rod inserted into the coil, the bulb in the circuit

• glows less brightly

• glows with same brightness (as before the rod is inserted)

• gets damaged

• glows more brightly

The output of a step down transformers is measured to be 48 V when connected to a 12 W bulb. The value of peak current is

• $\frac{1}{\sqrt{2}} \mathrm{A}$

• $\sqrt{2} \mathrm{A}$

• $\frac{1}{2\sqrt{2}} \mathrm{A}$

• $\frac{1}{4} \mathrm{A}$

In the circuit shown in the figure, the AC source gives a voltage V = 20 cos (2000t). Neglecting source resistance, the voltmeter and ammeter reading will be

• 1.68 V, 0.47 A

• 0 V, 1.47 A

• 5.6 V, 1.4 A

• 0 V, 1.4 A