Question

Derieve an expression for the energy stored in a parrallel plate capacitor

Answer 1

We know that electric field due to charged plate, E = Q/AEo
V=E*d (where d is the distance bet. the plates)
now, C=Q/V
C=Q/(Qd/AEo) (Eo is the permittivity of medium)
​ C=QAEo/Qd
C=AEo/d
therefore , Capacitance = Area of plate * Permittivity of medium
distance between the plates