Question

Derive an expression for capacitance of parallel plate capacitor with air as the medium between the plates.​

Answer 1

Let the two plates are kept parallel to each other separated be a distance d and cross-sectional area of each plate is A.  

Electric field by a single thin plate E'$\frac{ \alpha }{2eo} </p><p>$

Total electric field between the plates E =$\frac{ \alpha }{2ϵo} + \frac{ \alpha }{2 ϵo} </p><p>$

or E = $\frac{ \alpha }{ϵo}$

or E = $\frac{Q}{Aϵo}$

Potential difference between the plates V = Ed

Answer 2

Answer:

using the equation for potential difference and electric field between the two plates,v have derived the expression for the capacitance of parallel plate capacitors.

Explanation:

v can conclude the the capacitance of a parallel plate capacitor depends directly upon

*the area of the plates

*dielectric constant of the medium btw the plates

and inversely on

* the distance of separation between them.