Q. In the given figure distance of the point from $A$ where the electric field is zero is
A) $20\ cm$
B) $10\ cm$
C) $33\ cm$
D) None of these
Explanation
(c) Suppose electric field is zero at $N$. Hence $\left| E_{A} \right| = |E_{B}|$
Which gives $x_{1} = \frac{x}{\sqrt{\frac{Q_{2}}{Q_{1}}}\ + 1} = \frac{80}{\sqrt{\frac{20}{10}}\ + 1} = 33\ cm$
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.