Question

An electric field is generated in between two parallel hundred square meter electrodes that are separated by a distance of 2 centimeters.
We have the one plate charged to 5.0 nano coulomb and the other one. Exactly equal but opposite.

An additional square shaped surface is placed in between plates

Answer 1

$\Phi=ES'\cos \theta,$

$E=\frac Ud=\frac q{Cd}=\frac{qd}{d\varepsilon_0 S}=\frac q{\varepsilon_0 S},$

$\Phi=\frac{qS'}{\varepsilon_0 S}\cos \theta=8~\text{V}\cdot \text{m}.$