An electric dipole is placed at a distance of $2 \ cm$ from an infinite plane sheet having positive charge density $\sigma_0$. Choose the correct option from the following.

As shown in the figure,a particle $A$ of mass $2m$ and carrying charge $q$ is connected by a light rigid rod of length $L$ to another particle $B$ of mass $m$ and carrying charge $-q$. The system is placed in an electric field $\vec E$. The electric force on a charge $q$ in an electric field $\vec E$ is $\vec F = q \vec E$. After the system settles into equilibrium,one particle is given a small push in the transverse direction so that the rod makes a small angle $\theta_0$ with the electric field. Find the maximum tension in the rod.

An electric dipole with dipole moment $4 \times 10^{-9} \text{ Cm}$ is aligned at $60^{\circ}$ with the direction of a uniform electric field of magnitude $5 \times 10^4 \text{ NC}^{-1}$. Calculate the magnitude of the torque acting on the dipole.

Two charges $+q$ and $-q$ are placed at a distance $b$ apart as shown in the figure. The electric field at a point $P$ on the perpendicular bisector as shown is

Three charges $q, -2q$ and $q$ are placed at $(x=0, y=a, z=0)$,$(x=0, y=0, z=0)$ and $(x=a, y=0, z=0)$ respectively. What is the resultant electric dipole moment?

Point $P$ lies on the axis of a dipole. If the dipole is rotated by $90^o$ anticlockwise,the electric field vector $\vec{E}$ at $P$ will rotate by