An electric bulb rated as $100 \mathrm{~W}-220 \mathrm{~V}$ is connected to an ac source of rms voltage 220 V. The peak value of current through the bulb is :

<p>To find the peak current through the bulb, follow these steps:</p> <p><b>Step 1: Calculate the bulb's rms (root mean square) current:</b></p> <p>The formula to find the rms current is:</p> <p>$I_{\text{rms}}=\frac{P}{V}$</p> <p>Here, $P = 100 \text{ W}$ and $V = 220 \text{ V}$. Substitute these values into the formula:</p> <p>$I_{\text{rms}} = \frac{100\text{ W}}{220\text{ V}} \approx 0.455\text{ A}$</p> <p><b>Step 2: Convert the rms current to peak current:</b></p> <p>Use the following formula to find the peak current:</p> <p>$I_{\text{peak}} = I_{\text{rms}} \times \sqrt{2}$</p> <p>Substitute the value of $I_{\text{rms}}$ into the formula:</p> <p>$I_{\text{peak}} = 0.455 \times 1.414 \approx 0.64\text{ A}$</p> <p>The correct choice is <strong>0.64 A</strong> (Option B).</p>