Question

A 5.40 uF parallel-plate, air capacitor has a plate separation of 3.50 mm and is charged to a potential difference of 480 V. Calculate the energy density the region between the plates.

Answer 1

Energy density = 0.0831 J/m³

Step-by-step explanation:

Energy density of a capacitor is given by the expression

`u=(1)/(2)\epsilon E^2`

We have electric field ,

`E=(V)/(d)=(480)/(3.5* 10^(-3))=1.37* 10^5V/m`

Here there is no dielectric

So energy density,

`u=(1)/(2)\epsilon_0 E^2=(1)/(2)* 8.85* 10^(-12) * (1.37* 10^5)^2=8.31* 10^(-2)=0.0831 J/m^3`

Energy density = 0.0831 J/m³