Consider the charge configuration and spherical Gaussian surface as shown in the figure. When calculating the flux of the electric field over the spherical surface, the electric field will be due to

A hollow cylinder has a charge $q$ coulomb within it. If $\phi$ is the electric flux in units of voltmeter associated with the curved surface $B$, the flux linked with the plane surface $A$ in units of voltmeter will be 

A square surface of side $L$ metres is in the plane of the paper. A uniform electric field $E (\mathrm{volt} {\mathrm{m}}^{-1})$ also in the plane of the paper is limited only to the lower half of the square surface, (see figure). The electric flux in S.I. units associated with the surface is

The electric charges are distributed in a small volume. The flux of the electric field through a spherical surface of radius $10 \mathrm{cm}$ surrounding the total charge is $20 \mathrm{V} \mathrm{m}$. The flux over a concentric sphere of radius $20 \mathrm{cm}$ will be

What is the flux through a cube of side $a$ if a point charge of $q$ is at one of its corner?

If the charge on a capacitor is increased by $2$ coulomb, the energy stored in it increases by $21 \% .$ The original charge on the capacitor is 

A parallel plate capacitor with air between the plates has a capacitance of $9 \mathrm{pF}$. The separation between its plates is $d$. The space between the plates is now filled with two dielectrics. One of the dielectrics has constant $k_1=3$ and thickness $\frac{d}{3}$ while the other one has dielectric constant $k_2=6$ and thickness $\frac{2d}{3}$. Capacitance of the capacitor is now

A parallel plate air capacitor has capacity $C$ farad, potential $V$ volt and energy $E$ joule. When the gap between the plates is completely filled with dielectric

A capacitor is charged by a battery. The battery is removed and another identical uncharged capacitor is connected in parallel. The total electrostatic energy of resulting system