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=If the rms current in a $50 \mathrm{~Hz} \mathrm{AC}$ circuit is $5 \mathrm{~A}$, the value of the current $1 / 300 \mathrm{~s}$ after its value becomes zero is
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$5 \sqrt{3} / 2 \mathrm{~A}$
$5 \sqrt{3} / 2 \mathrm{~A}$
As given that, $\mathrm{v}=50 \mathrm{~Hz}, \mathrm{I}_{\mathrm{rms}}=5 \mathrm{~A}$ $t=\frac{1}{300} s$
As we know that $\mathrm{I}_{\mathrm{rms}}=\frac{\mathrm{I}_0}{\sqrt{2}}$
$\mathrm{I}_0=$ Peak value $=\sqrt{2} . \mathrm{I}_{\mathrm{ms}}=\sqrt{2} \times 5$ $\mathrm{I}_0=5 \sqrt{2} \mathrm{~A}$
$$
\begin{aligned}
&\text { at, } \begin{aligned}
\mathrm{t}=\frac{1}{300} \mathrm{sec}, \mathrm{I} &=\mathrm{I}_0 \sin \omega \mathrm{t}=5 \sqrt{2} \sin 2 \pi \mathrm{vt} \\
&=5 \sqrt{2} \sin 2 \pi \times 50 \times \frac{1}{300}
\end{aligned} \\
&\mathrm{I}=5 \sqrt{2} \sin \frac{\pi}{3}=5 \sqrt{2} \times \frac{\sqrt{3}}{2}=5 \sqrt{3 / 2} \mathrm{Amp} \\
&\mathrm{I}=\left(5 \sqrt{\frac{3}{2}}\right) \text { Amp }
\end{aligned}
$$
As we know that $\mathrm{I}_{\mathrm{rms}}=\frac{\mathrm{I}_0}{\sqrt{2}}$
$\mathrm{I}_0=$ Peak value $=\sqrt{2} . \mathrm{I}_{\mathrm{ms}}=\sqrt{2} \times 5$ $\mathrm{I}_0=5 \sqrt{2} \mathrm{~A}$
$$
\begin{aligned}
&\text { at, } \begin{aligned}
\mathrm{t}=\frac{1}{300} \mathrm{sec}, \mathrm{I} &=\mathrm{I}_0 \sin \omega \mathrm{t}=5 \sqrt{2} \sin 2 \pi \mathrm{vt} \\
&=5 \sqrt{2} \sin 2 \pi \times 50 \times \frac{1}{300}
\end{aligned} \\
&\mathrm{I}=5 \sqrt{2} \sin \frac{\pi}{3}=5 \sqrt{2} \times \frac{\sqrt{3}}{2}=5 \sqrt{3 / 2} \mathrm{Amp} \\
&\mathrm{I}=\left(5 \sqrt{\frac{3}{2}}\right) \text { Amp }
\end{aligned}
$$
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