Question

Five identical conducting plates, $1.2,3,4$ and $5$ are fixed parallel plates equidistant from each other (see figure). A conductor connects plates $2$ and $5$ while another conductor joins $1$ and $3$. The junction of $1$ and $3$ and the plate $4$ are connected to a source of constant emf $V_o$. Find the effective capacitance of the system between the terminals of source where $d$ is the distance between any two successive plates.

Answer 1

$C=\frac{{ϵ}_{o}A}{d}$ (between two successive plates).
$C_{net}=C+\frac{\left(2C\right)\left(C\right)}{2C+C}=\frac{5}{3}\frac{{ϵ}_{o}A}{d}$