Q. Point charges $+ 4q,\ - q$ and $+ 4q$ are kept on the $x -$axis at points $x = 0,\ x = a$ and $x = 2a$ respectively, then
A) Only $q$ is in stable equilibrium
B) None of the charges are in equilibrium
C) All the charges are in unstable equilibrium
D) All the charges are in stable equilibrium
Explanation
(c) Force on each charge is zero. But if any of the charge is displaced, the net force starts acting on all of them
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.