Question

Two point charges $+q_{1}$ and $+q_{2}$ are placed a finite distance ' $d$ ' apart. It is desired to put a third charge $q_{3}$ in between these two charges so that $q_{3}$ is in equilibrium. This is

• A. possible only if $q_{3}$ is negative.
• B. possible only if $q_{3}$ is positive.
• C. possible irrespective of the sign of $q_{3}$.
• D. not possible at all.

Answer 1

Answer: (C)

At null point $\vec{E}=0$
$\therefore $ any charge placed at that point will remain in equilibrium.