The energy stored in a capacitor is the work done to move charge against the electric field between the plates. It’s an example of potential energy, which in this case, is stored in the electric field itself. Energy density is a measure of how much energy is stored in a given space.
The energy UC stored in a capacitor is electrostatic potential energy and is thus related to the charge Q and voltage V between the capacitor plates. A charged capacitor stores energy in the electrical field between its plates. As the capacitor is being charged, the electrical field builds up.
A simple example of capacitors as an energy storage device is parallel plate capacitors. It is generally referred to as Condenser. In this article, we will discuss the formula and derivation of energy stored in a capacitor.
Calculate the change in the energy stored in a capacitor of capacitance 1500 μF when the potential difference across the capacitor changes from 10 V to 30 V. Step 1: Write down the equation for energy stored in terms of capacitance C and p.d V Step 2: The change in energy stored is proportional to the change in p.d Step 3: Substitute in values
The work done is equal to the product of the potential and charge. Hence, W = Vq If the battery delivers a small amount of charge dQ at a constant potential V, then the work done is Now, the total work done in delivering a charge of an amount q to the capacitor is given by Therefore the energy stored in a capacitor is given by Substituting
Figure 8.4.1: The capacitors on the circuit board for an electronic device follow a labeling convention that identifies each one with a code that begins with the letter “C.” The energy UC stored in a capacitor is electrostatic potential energy and is thus related to the charge Q and voltage V between the capacitor plates.