An electric dipole having each charge of magnitude $2 \mu C$ is placed in an electric field of intensity $8 \times 10^{4} \ N/C$. If the maximum torque acting on the dipole is $4 \times 10^{-3} \ N \cdot m$,the length of the dipole is: (in $mm$)

$A$ point particle of charge $Q$ is located at $P$ along the axis of an electric dipole $1$ at a distance $r$ as shown in the figure. The point $P$ is also on the equatorial plane of a second electric dipole $2$ at a distance $r$. The dipoles are made of opposite charges $q$ separated by a distance $2a$. For the charged particle at $P$ not to experience any net force,which of the following correctly describes the situation?

$A$ 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 $:$

Explain the positions (orientations) of a dipole in stable equilibrium,unstable equilibrium,and when the potential energy is zero.

The angle between the electric dipole moment of a dipole and the electric field strength due to it on the equatorial line is (in $^{\circ}$)

The angle between the dipole moment and electric field at any point on the equatorial plane is (in $^{\circ}$)