Q 12-02-019NEETJEE MainEAMCET 2008 (Engineering)Easy
Two charges $q$ and $-q$ are kept apart. Then at any point on the perpendicular bisector of the line joining the two charges
Answer: (B) the electric potential is zero
Every point on the perpendicular bisector is equidistant from the two charges, so their potentials $\dfrac{kq}{r}$ and $-\dfrac{kq}{r}$ cancel: $V = 0$.
The fields do not cancel: their components along the bisector cancel, but the components parallel to the dipole axis add. So $E \neq 0$.
Solution by Sreeraj P, M.Sc Physics