Answer
$1 Nm^{2}C^{-1}$
Work Step by Step
As we know,
Electric flux $\phi$ through any surface is,
$ \phi= E.A=EAcos\theta$
Here, $\theta=\frac{\pi}{2}-30^{\circ}=\frac{\pi}{2}-\frac{\pi}{6}=\frac{\pi}{3}$,
$E=200 N/C$ and $A= 10^{-2}m^{2}$ .
Hence,
$\phi=200 \times10^{-2}\times\frac{\pi}{3}$
$=200 \times10^{-2}\times cos(\frac{\pi}{3})$
$=2\times\frac{1}{2}=1 Nm^{2}C^{-1}$
