An infinitely long uniform line charge distribution of charge per unit length $\lambda$ lies parallel to the $y$-axis in the $y-z$ plane at $z=\frac{\sqrt{3}}{2} a$ (see figure). If the magnitude of the flux of the electric field through the rectangular surface $A B C D$ lying in the $x-y$ plane with its center at the origin is $\frac{\lambda L }{ n \varepsilon_0}\left(\varepsilon_0=\right.$ permittivity of free space $)$, then the value of $n$ is

A point charge $+10\; \mu \,C$ is a distance $5 cm$ directly above the centre of a square of side $10 \;cm ,$ as shown in Figure. What is the magnitude of the electric flux through the square?

How does the no. of electric field lines passing through unit area depend on distance ?

A point charge of $2.0\; \mu \,C$ is at the centre of a cubic Gaussian surface $9.0\; cm$ on edge. What is the net electric flux through the surface?

A charge $Q$ is situated at the comer of a cube, the electric flux passed through all the six faces of the cube is

What will be the total flux through the faces of the cube as in figure with side of length $a$ if a charge $q$ is placed at ?

$(a)$ $A$ $:$ a corner of the cube.

$(b)$ $B$ $:$ midpoint of an edge of the cube.