Define capacitance of a capacitor. Derive an expression for the capacitance of a
parallel plate capacitor filled with dielectric (k) between the plates.
Answers
Answer:
What would you like to ask?
12th
Physics
Electrostatic Potential and Capacitance
Effects of Dielectrics in Capacitors
Define electric capacity. D...
PHYSICS
Define electric capacity. Derive an expression for the capacitance of a parallel plate capacitor in which a dielectric medium of dielectric constant K fills the space between the plates. Draw the necessary diagram.
MEDIUM
Share
Study later
VIDEO EXPLANATION
ANSWER
Capacitance or electric capacity indicates the ability of a system to store charge. It is defined as the ratio of charge stored in the conductors to the potential difference across the conductors. Its SI unit is Farad (F). Hence:
C=
V
Q
To derive the expression of capacitance of parallel plate capacitor of conductor area A and distance between the conductors as d with a dielectric of dielectric constant K carrying a charge Q and potential difference V, refer to the attached figure.
Electric field between plates of the capacitor can be found using Gauss Law.
E=
Kε
o
σ
E=
Kε
o
A
Q
as σ=
A
Q
Electric field is defined as the gradient of potential.
E=
d
V
⟹V=
Kε
o
A
Qd
By definition of capacitance,
C=
V
Q
=
d
Kε
o
A
I HOPE IT HELP YOU!