Question

A and B are two points on the axis and the perpendicular bisector respectively of an electric dipole. A and B are far away from the dipole and at equal distances from its centre. The fields at A and B i.e. $\overrightarrow{E_A}and\overrightarrow{E_B}$ are respectively such that

• A. $\overrightarrow{E_A}=\overrightarrow{E_B}$
• B. $\overrightarrow{E_A}=2\overrightarrow{E_B}$
• C. $\overrightarrow{E_A}=-2\overrightarrow{E_B}$
• D. $\overrightarrow{E_A}=\frac{1}{2}\overrightarrow{E_B}$

Answer 1

The correct option is C $\overrightarrow{E_A}=-2\overrightarrow{E_B}$

It will be cleared Heat electric field dual to an electric dipole at axial point is $2Kp/r^3$ while at a point on perpendicularity bisector is $Kp/r^3$. So, if electric field at point $A$ is $E$ then electric field at point $B$ will be $E/2$.

Now, $E_A=-2E_B$