A charge $q$ is placed at the centre of a cube whose top face is open (it has only $5$ faces). Calculate the total electric flux passing through the cube.

An electric flux of $-6\times {10}^{-3} \mathrm{N} {\mathrm{m}}^2 {\mathrm{C}}^{-1}$ passes normally through a spherical Gaussian surface of radius $10 \mathrm{cm}$, due to a point charge placed at its centre.

What is the charge enclosed by the Gaussian surface?

An electric flux of $6\times {10}^3 {\mathrm{Nm}}^2{\mathrm{C}}^{-1}$ passes through a spherical Gaussian surface of radius $10 \mathrm{cm}$ due to the charge placed at its centre.

If the radius of the Gaussian surface is doubled how much flux would pass through the surface?

A Gaussian surface encloses two of the four positively charged particles as shown in the figure. Which of the particles contribute to the electric field at a point $P$ on the surface?

Two large, thin metal plates are parallel and close to each other. The plates have surface charge densities of opposite signs and magnitude $17.0\times {10}^{-12} \mathrm{C} {\mathrm{m}}^{-2}$ on their inner faces. What is electric field between the plates?

Plot the graph between electric field inside a conducting sphere versus distance from its centre.