An electric dipole of dipole moment $\vec{P}$ is placed parallel to a uniform electric field of intensity $\vec{E}$. On rotating it through $180^{\circ}$,the amount of work done is . . . . . . .

When a test charge is brought in from infinity along the perpendicular bisector of an electric dipole,the work done is ..........

An electric dipole is placed at the centre of a sphere. Mark the correct answer.

An electric dipole with dipole moment $5 \times 10^{-6} \ Cm$ is aligned with the direction of a uniform electric field of magnitude $4 \times 10^5 \ N/C$. The dipole is then rotated through an angle of $60^{\circ}$ with respect to the electric field. The change in the potential energy of the dipole is (in $J$)

An electric dipole of length $2 \ cm$ is placed with its axis making an angle of $60^{\circ}$ to a uniform electric field of $10^{5} \ N/C$. If it experiences a torque of $8 \sqrt{3} \ Nm$,calculate the magnitude of the charge on the dipole. (Given: $\sin 60^{\circ} = \frac{\sqrt{3}}{2}$)

Two point dipoles $p \hat{k}$ and $\frac{p}{2} \hat{k}$ are located at $(0, 0, 0)$ and $(1 \text{ m}, 0, 2 \text{ m})$ respectively. The resultant electric field due to the two dipoles at the point $(1 \text{ m}, 0, 0)$ is