Suppose that intensity of a laser is
$\left(\frac{315}{\pi}\right) \mathrm{W} / \mathrm{m}^{2}$. The rms electric field, in units
of $\mathrm{V} / \mathrm{m}$ associated with this source is close to the nearest integer is
$\left(\epsilon_{0}=8.86 \times 10^{-12} \mathrm{C}^{2} \mathrm{Nm}^{-2} ; \mathrm{c}=3 \times 10^{8} \mathrm{~ms}^{-1}\right)$
$\mathrm{I}=\epsilon_{0} \mathrm{E}_{\mathrm{rms}}^{2} \mathrm{C}$
$\mathrm{E}_{\mathrm{rms}}^{2}=\frac{\mathrm{I}}{\epsilon_{0} \mathrm{C}}$
$=\frac{315}{\pi \in_{0}} \times \frac{1}{\mathrm{C}}$
$=\frac{4 \times 315}{4 \pi \in_{0}} \times \frac{1}{3 \times 10^{8}}$
$=\frac{4 \times 315 \times 9 \times 10^{9}}{3 \times 10^{8}}$
$\mathrm{E}_{\mathrm{rms}}^{2}=4 \times 315 \times 30$
$E_{\mathrm{rms}}=2 \sqrt{315 \times 30}$
$=194.42$
Ans. $194.00$