A charged particle $q$ is placed at the centre $O$ of cube of length $L \left(ABCDEFGH\right)$. Another same charge $q$ is placed at a distance $L$ from $O$. Then the electric flux through $BCFG$ is

A ring of radius $R$ is placed in the plane with its centre at origin and its axis along the $x$ axis and having uniformly distributed positive charge. A ring of radius $r\left(\ll R\right)$ and coaxial with the larger ring is moving along the axis with constant velocity. Then, the variation of electric flux $\varphi$ passing through the smaller ring with position will be best represented by,

Electric charge is uniformly distributed along a long straight wire of radius $1 \mathrm{mm}$. The charge per $\mathrm{cm}$ length of the wire is $Q$ coulomb. Another cylindrical surface of radius $50 \mathrm{cm}$ and length $1 \mathrm{m}$ symmetrically encloses the wire as shown in the figure. The total electric flux passing through the cylindrical surface is, 

In a region of space having a spherically symmetric distribution of charge, the electric flux enclosed by a concentric spherical Gaussian surface varies with a radius $r$ as 
$\mathrm{\varphi }=\left\{\begin{array}{ll}\frac{{\mathrm{\varphi }}_0{r}^2}{R^3},& r\le R\\ {\mathrm{\varphi }}_0,& r>R\end{array}\right.$ where $R$ and ${\mathrm{\varphi }}_0$ are the constants.

The electric field strength in the region is given as, 

Electric field is given by $\overrightarrow{E}=\left(8\hat{\mathrm{i}}+4\hat{\mathrm{j}}+3\hat{\mathrm{k}}\right) \mathrm{N} {\mathrm{C}}^{-1}$. Electric flux through surfaces of area $100 {\mathrm{m}}^2$ layer in $X\mathit{-}Y$ plane, $Y-Z$ plane and $X-Z$ plane are in ratio