Charged Plates
  • As mentioned previously, two parallel plates that have been oppositely charged produces a uniform electric field.
  • This means that any charge at any place between the two plates has the exact same force acting upon it.

To find out what the uniform Electric field strength is quantitatively:

  • Recall that the force on a charged particle is given by: $F = qE$
    • Where, E is the electric field strength
  • Also, that Voltage is the change in potential energy per unit charge : $W = qV$
  • As $W = Fd$:
(1)
\begin{equation} qV = Fd \end{equation}
(2)
\begin{equation} qV = qEd \end{equation}
(3)
\begin{equation} V = Ed \end{equation}

Therefore:

(4)
\begin{align} E = \frac{V}{d} \end{align}