The angle between the electric lines of force and the equipotential surface is (in $^{\circ}$)

$A$ circle of radius $R$ is drawn with a charge $+q$ at the centre. $A$ charge $q_0$ is moved from point $B$ to $C$ along the circumference of the circle. The work done is:

What is an equipotential surface? Draw equipotential surfaces for:
$(1)$ $A$ single point charge
$(2)$ $A$ dipole (charges $+q$ and $-q$ at a small distance)
$(3)$ Two $+q$ charges at a small distance
$(4)$ $A$ uniform electric field.

The figure shows two equipotential lines in the $XY$ plane for an electric field. The scale is shown. The $X$-component $E_x$ and $Y$-component $E_y$ of the electric field in the space between the equipotential lines are respectively:

$A$ point charge is placed at point $P$ as shown in the figure. $A$ hollow conducting sphere is placed in the electric field produced by it. If $V_A$,$V_B$,and $V_C$ are the potentials at points $A$,$B$,and $C$ respectively,then:

In the electric field of a point charge $+q$, a certain charge is carried from point $A$ to points $B, C, D$ and $E$ along the paths shown in the figure. Then the work done: