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 dipole.

What is an equipotential surface ? Draw an equipotential surfaces for a

$(1)$ single point charge

$(2)$ charge $+ \mathrm{q}$ and $- \mathrm{q}$ at few distance (dipole)

$(3)$ two $+ \mathrm{q}$ charges at few distance

$(4)$ uniform electric field.

Figure shows a set of equipotential surfaces. The magnitude and direction of electric field that exists in the region is .........

Three equal charges are placed at the corners of an equilateral triangle. Which of the graphs below correctly depicts the equally-spaced equipotential surfaces in the plane of the triangle? (All graphs have the same scale.)

Two charges $2 \;\mu\, C$ and $-2\; \mu \,C$ are placed at points $A$ and $B\;\; 6 \;cm$ apart.

$(a)$ Identify an equipotential surface of the system.

$(b)$ What is the direction of the electric field at every point on this surface?