Question

consider a point charge + Q placed at the origin and another point charge minus Q placed at the distance of 9 metre from the charge + Q determine the point between the two charged at which electric potential is zero​

Answer 1

Potential at any point is given by V=4πϵodq

where d is the distance of that point from the charge.

Thus potential at the midpoint P Vp=4πϵoaq+4πϵoaq

∴ Vp=2πϵoaq