Question
A parallel$-$plate air capacitor has an area $2 \times 10^{-4} m ^2$ and the separation between the two plates is $1 \ mm$. Find its capacitance.
✓
Answer
Data : $A=2 \times 10^{-4} m ^2, d =1 \ mm =10^{-3} m$, $\varepsilon_0=8.85 \times 10^{-12} C ^2 / N \cdot m ^2, k =1($ for air$)$
The capacitance,
$C =\frac{A k \varepsilon_0}{d}$
$=\frac{\left(2 \times 10^{-4}\right)(1)\left(8.85 \times 10^{-12}\right)}{10^{-3}}$
$=1.77 \times 10^{-12} F $
$=1.77 pF$
The capacitance,
$C =\frac{A k \varepsilon_0}{d}$
$=\frac{\left(2 \times 10^{-4}\right)(1)\left(8.85 \times 10^{-12}\right)}{10^{-3}}$
$=1.77 \times 10^{-12} F $
$=1.77 pF$
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