Home
Class 12
PHYSICS
Obtain the expression for the energy sto...

Obtain the expression for the energy stored in a parallel plate capacitor.

Text Solution

Verified by Experts

Energy stored in the vapacitor
`U_E = 1/2 CV^2" …(1)"`
This is rewritten as using `C =(E_(0)A)/d "& Ed = V"` n
`U_E = 1/2 ((epsi_(0)A)/(d))("ED")^2 = 1/2 epsi_(0) ("Ad")E^(2)" …(2)"`
where Ad = volume of the space between the capacitor plates. The energy stored per unit volume of space is defined as energy density
`u_E = U/(.Volume")` From equation (4).
We get
`u_E = 1/2 epsi_0 E^2" ....(3)"`
The energy density depends only on the electric field and not on the size of the plates of the capacitor.
Promotional Banner

Similar Questions

Explore conceptually related problems

A. A device to store electrical charge is called a. Transformer b. Capacitor c. Resistor d. Inductor B. What is meant by energy density of a parallel plate capacitor? C. Derive an expression for the energy stored in a parallel plate capacitor. D. What is the area of the plates of a 0.1muF parallel plate air capacitor, given that the separation between the plates is 0.1 mm.

Keeping the voltage of the charging source constant, what would be the percentage change in the energy stored in a parallel plate capacitor if the separation between its plates is decreased by 10%?

Obtain an expression for capacitance for a parallel plate capacitor.

a. Obtain the expression for the magnetic energy stored in a solenoid in terms of magnetic field B, area A and length l of the solenoid. b. How does this magnetic energy compare with the electrostatic energy stored in a capacitor?

Obtain the expression for capacitance for capacitance for a parallel plate capacitor .

Explain in detail the effect of a dielectric placed in a parallel plate capacitor.

The energy stored in a capacitor is given by