You are given a dipole of charge $+q$ and $-q$ separated by a distance $2R$. $A$ sphere '$A$' of radius ' $R$ ' passes through the centre of the dipole as shown below and another sphere '$B$' of radius ' $2R$ ' passes through the charge $+q$. Then the electric flux through the sphere '$A$' is

If the radius of the spherical Gaussian surface is increased, then the electric flux due to a point charge enclosed by the surface

If the electric flux entering and leaving an enclosed surface are $\phi_1$ and $\phi_2$ respectively,the electric charge inside the surface will be

How much electric flux will come out through a surface $S = 10\hat{j}$ kept in an electrostatic field $\vec{E} = 2\hat{i} + 4\hat{j} + 7\hat{k}$ units?

$A$ metallic spherical shell has an inner radius $R_1$ and outer radius $R_2$. $A$ charge $Q$ is placed at the centre of the spherical cavity. What will be the surface charge density on the inner surface?

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 $\frac{\lambda L }{ n \varepsilon_0}$ (where $\varepsilon_0$ is the permittivity of free space),then the value of $n$ is