Question

Two point charges are kept at a certain distance from one another. Figure represents the variation of the potential along the straight line connecting the two charges. At what point is the electric field zero?

• A. $1$
• B. $2$
• C. $3$
• D. All of these

Answer 1

The correct option is D All of these

The electric field is $E=-\frac{dV}{dx}$
At $1$ and $2$, $V=0$ So the electric filed at $1$ and $2$ may be zero.
At $3$, V is maximum, so $\frac{dV}{dx}=0$, thus the electric field must be zero at $3$.