What is the potential energy of two equal positive point charges of $1\,\mu C$ each,held $1\, m$ apart in air?

Three charges $Q, (+q)$ and $(+q)$ are placed at the vertices of an equilateral triangle of side $l$ as shown in the figure. If the net electrostatic potential energy of the system is zero,then $Q$ is equal to

The electrostatic potential due to an electric dipole at a distance '$r$' varies as:

The value of electric potential at any point due to an electric dipole is:

Three infinitely long linear charges of charge density $\lambda$,$\lambda$,and $-2\lambda$ are placed in space. $A$ point in space is specified by its perpendicular distances $r_1$,$r_2$,and $r_3$ respectively from the linear charges. For the points which are equipotential:

The electric potential at a point on the axis of an electric dipole depends on the distance $r$ of the point from the dipole as