Which of the following figure shows the correct equipotential surfaces of a system of two positive charges?

Assertion $(A):$ A spherical equipotential surface is not possible for a point charge.

Reason $(R):$ A spherical equipotential surface is possible inside a spherical capacitor.

A point charge $+Q$ is placed just outside an imaginary hemispherical surface of radius $R$ as shown in the figure. Which of the following statements is/are correct?

(IMAGE)

$[A]$ The electric flux passing through the curved surface of the hemisphere is $-\frac{\mathrm{Q}}{2 \varepsilon_0}\left(1-\frac{1}{\sqrt{2}}\right)$

$[B]$ Total flux through the curved and the flat surfaces is $\frac{Q}{\varepsilon_0}$

$[C]$ The component of the electric field normal to the flat surface is constant over the surface

$[D]$ The circumference of the flat surface is an equipotential

Draw an equipotential surface for a point charge.

The equation of an equipotential line in an electric field is $y = 2x$, then the electric field strength vector at $(1, 2)$ may be

Write the characteristics of equipotential surface.