The electric potential at a point on the axis of an electric dipole is proportional to $[r=$ distance between the centre of the electric dipole and the point].

When is the torque on an electric dipole in an electric field maximum?

$A$ dipole with two electric charges of $2 \ \mu C$ magnitude each,with separation distance $0.5 \ \mu m$,is placed between the plates of a capacitor such that its axis is parallel to an electric field established between the plates when a potential difference of $5 \ V$ is applied. Separation between the plates is $0.5 \ mm$. If the dipole is rotated by $30^{\circ}$ from the axis,it tends to realign in the direction due to a torque. The value of torque is $:$

Two charges of $+25 \times 10^{-9} \, C$ and $-25 \times 10^{-9} \, C$ are placed $6 \, m$ apart. Find the ratio of the electric field intensity at a point $4 \, m$ from the center of the electric dipole on the $(i)$ axial line and $(ii)$ equatorial line.

When three electric dipoles are near each other,they each experience the electric field of the other two,and the three-dipole system has a certain potential energy. The figure below shows three arrangements $(1)$,$(2)$,and $(3)$ in which three electric dipoles are side by side. All three dipoles have the same magnitude of electric dipole moment,and the spacings between adjacent dipoles are identical. If $U_1$,$U_2$,and $U_3$ are potential energies of the arrangements $(1)$,$(2)$,and $(3)$ respectively,then:

The force on a charge situated on the axis of a dipole is $F$. If the charge is shifted to double the distance,the new force will be