A hollow cylinder has a charge $q$ coulomb within it. If $\phi$ is the electric flux in units of $volt-meter$ associated with the curved surface $B,$ the flux linked with the plane surface $A$ in units of $V-m$ will be
$\;\frac{q}{{2{\varepsilon _0}}}$
$\frac{\phi}{3}$
$\;\frac{q}{{{\varepsilon _0}}}$ -$\phi$
$\frac{1}{2}$($\frac{q}{{{\varepsilon _0}}}$ -$\phi$)
A charge $q$ is placed at the centre of the open end of cylindrical vessel. The flux of the electric field through the surface of the vessel is
A sphere encloses an electric dipole with charge $\pm 3 \times 10^{-6} \;\mathrm{C} .$ What is the total electric flux across the sphere?......${Nm}^{2} / {C}$
If the electric field intensity in a fair weather atmosphere is $100 \,V / m$, then the total charge on the earth's surface is ............ $C$ (radius of the earth is $6400\,km$ )
A charged particle $q$ is placed at the centre $O$ of cube of length $L$ $(A\,B\,C\,D\,E\,F\,G\,H)$. Another same charge $q$ is placed at a distance $L$ from $O$.Then the electric flux through $BGFC$ is
A charge $+q$ is placed somewhere inside the cavity of a thick conducting spherical shell of inner radius $R_1$ and outer radius $R_2$. A charge $+Q$ is placed at a distance $r > R_2$ from the centre of the shell. Then the electric field in the hollow cavity