Question

A charge of 1 µC is given to one plate of a parallel-plate capacitor of capacitance 0⋅1 µF and a charge of 2 µC is given to the other plate. Find the potential difference developed between the plates.

Answer 1

Charges on the plates:
$$\begin{gathered} q_1=1\mathrm{\mu C}=1\times {10}^{-6}\mathrm{C}\mathit{} \\ {q}_2=2\mathrm{\mu C}=2\times {10}^{-6}\mathit{}\mathrm{C} \end{gathered}$$

The effective charge on the capacitor is given by
$q_{\mathrm{net}}=\frac{q_2-q_1}{2}=\frac{(2-1)\times {10}^{-6}}{2}=0.5\times {10}^{-6}\mathrm{C}$

The potential difference is given by
$V=\frac{q_{\mathrm{net}}}{C}=\frac{0.5\times {10}^{-6}}{0.1\times {10}^{-6}}=5\mathrm{V}$