Why in the region where the spheres overlap, the net electric field is not zero but constant. I am asking this because:
- the net charge inside the overlap region is zero as there are equal number of positive and negative charges
- if a closed surface does not have any charge inside where an electric field line can terminate, then any electric field line entering the surface at one point must necessarily exit at some other point of the surface, then the electric flux through the surface is zero and hence electric field is zero.
Now, the overlap region can be imagined as a "closed surface" with no charge(as the net charge is zero) and we can say that the charge outside the overlap region is "external charge". As per Gauss's Law :
The electric flux through a closed surface due to a charge outside that surface is zero.
Charges are enclosed, but because the net charge included is zero, the net flux through the closed surface is also zero.
I am unable to understand where I am wrong; maybe in Gauss's law by closed surface they are talking about hollow closed surface.