Energy Stored in Capacitor - Graphically
In our daily life, we come across various things when an electrical energy storing device is needed.
And the battery is the most common device used to store the energy.
But, the storage of electrical energy is not limited to battery only.
Some other devices also exist which is used to store energy.
For example, an inductor.
And a Capacitor.
Let's analyze the energy stored in the capacitor graphically.
Suppose we have a parallel plate capacitor with a dielectric in it and we connected it to a battery having a voltage
$V$
.
This voltage will charge the capacitor by the charge
$Q$
.
The potential difference across the plates of a capacitor is directly proportional to the charge stored on the plates.
This gives a straight line through the origin of a voltage-charge graph.
The area under this curve gives energy stored in the capacitor.
Therefore, the energy stored in the capacitor is calculated by
$U$
.
And this energy equals the work done.
So, the work done in charging the capacitor is calculated by
$W$
.
But, as the
$Q=C×V$
. So, the work
$W$
will be as above.
On putting
$V=CQ $
in the equation, we get as above.
So, we can say that work done to charging a capacitor
$W$
will be as above.
Revision
The area under this curve gives energy stored in the capacitor.
The energy stored in the capacitor is given by
$U$
and this energy equals the work done by the capacitor.
The work done to charging a capacitor
$W$
will be given by,
The End