Question

Question 2.24: What is the area of the plates of a 2 F parallel plate capacitor, given that the separation between the plates is 0.5 cm? [You will realize from your answer why ordinary capacitors are in the range of µF or less. However, electrolytic capacitors do have a much larger capacitance (0.1 F) because of very minute separation between the conductors.]

Class 12 - Physics - Electrostatic Potential And Capacitance Electrostatic Potential And Capacitance Page-89

Answer 1

use formula $\boxed{\bf{C=\frac{\epsilon_0A}{d}}}$
Here, C is the capacitance of capacitor
$\epsilon_0$ is the permittivity of medium in vaccum ,A is the cross section area of parallel plate capacitors and d is the separation between plates.

$so,A=\frac{C.d}{\epsilon_0}$
A = 2 × 0.5 × 10^-2/8.85 × 10^-12
A = 1.13 × 10^9 m² = 1130 km²
this is why ordinary capacitors in the range of micro farad or less.