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

Explanation

Here A = ? C = 2F
d = 0.5 cm `= 5 xx 10^(-3) m`
As `C = (epsilon_(0) A)/(d)`
`:. A = (cd)/(epsilon_(0)) = (2 xx 5 xx 10^(-3))/(8.85 xx 10^(-12))`
`1.13 xx 10^(9) m^(2)`
which is too large.
That is why ordinary capacirots are in the range of `mu F` or less. However in electrolytic capacitors d is too small. Therefore their capacitance is much larger (0.1 F)