Question

Two infinite and parallel sheets of charge have the same surface density. What is the field in the region between the sheets

Answer 1

We know that

Surface charge density

$\sigma=\frac{Q}{A}$

Now plate left side electric field

$E_L=\frac{-\sigma}{2\epsilon_0}+\frac{\sigma}{2\epsilon_0}=0$

Plate right side electric field

$E_R=\frac{\sigma}{2\epsilon_0}-\frac{\sigma}{2\epsilon_0}=0$

Plate mid point electric field

$E_m=\frac{\sigma}{2\epsilon_0}+\frac{\sigma}{2\epsilon_0}=\frac{\sigma}{\epsilon_0}$

To infinite and parallel sheet between electric field

$E_m=\frac{\sigma}{2\epsilon_0}+\frac{\sigma}{2\epsilon_0}=\frac{\sigma}{\epsilon_0}$