Calculate the capacitance of two parallel plates. Enter the total area and the separation distance of the plates to calculate capacitance.
The following formula can be used to calculate the capacitance of parallel plates:
C = ε * A / s
- Where C is capacitance (farads)
- ε is dielectric permittivity (farads per meter) ( 10^(-12) farads/meter for a vacuum.)
- A is the area of the overlapping plates
- s is the distance between the plates.
What is capacitance
Capacitance is the ability of an object or system to store electricity. More specifically, an electric charge. This value depends on the geometry of the capacitor and the dielectric material between plates. A larger surface area yields a larger capacitance. A smaller distance between plates also yields a larger capacitance and vise versa.
The SI units of capacitance is the farad which is denoted by the symbol, F. A farad is a measure of capacitance, and therefore, 1 farad is equal to 1 coulomb of electric charge at a difference of 1 volt.
The real world use of capacitance is in capacitors. These are devices that store electrical energy in an electric field. The most common use of capacitors is in energy storage. A capacitor can act as a temporary battery when electric supply is cut off to a device. Capacitors are also used in digital memory.
How to calculate capacitance
Calculating capacitance is pretty straight forward. First, you need to measure the total area of the overlapping plates. Next, you need to calculate the dielectric permittivity of the capacitor. This is the most difficult, and in most cases the value for a vacuum is used for simplicity. Finally measure the total separation distance and enter in the formula above.
You can also simply use the above calculator. This calculator does not assume a vacuum. If you wish you calculate the capacitance in a vacuum, simply enter 8.854 pF/m for the permittivity.