An electric dipole having dipole moment $P = q \times 2\ell$ is placed in a uniform electric field $E$. The dipole moment is along the direction of the field. The force acting on it and its potential energy are respectively

$A$ 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 $:$

Three point charges $+q, -2q$ and $+q$ are placed at points $(x = 0, y = a, z = 0)$,$(x = 0, y = 0, z = 0)$ and $(x = a, y = 0, z = 0)$ respectively. The magnitude and direction of the electric dipole moment vector of this system are:

An electric dipole is placed in a uniform electric field $\vec{E}$ of magnitude $40\ N/C$. The graph shows the magnitude of the torque $\tau$ on the dipole versus the angle $\theta$ between the field $\vec{E}$ and the dipole moment $\vec{p}$. The magnitude of the dipole moment $\vec{p}$ is equal to:

Two point charges of same magnitude and opposite sign are fixed at points $A$ and $B$. $A$ third small point charge is to be balanced at point $P$ by the electrostatic force due to these two charges. The point $P$

Two charges $+3.2 \times 10^{-19} \text{ C}$ and $-3.2 \times 10^{-19} \text{ C}$ placed at $2.4 \text{ Å}$ apart form an electric dipole. It is placed in a uniform electric field of intensity $4 \times 10^5 \text{ V/m}$. The electric dipole moment is