Electricity & Megnetism

# Electrostatic Capacity

According to the definition of the Aurélio dictionary, the word capacity has the following definitions: 1 – Volume or interior scope of an empty body. 2 – Quality that the person or thing has to satisfy for a certain purpose.

This second definition refers to anyone we know, for example: a doctor has the technical and personal capacity to take good care of his patients; a seller must have the ability to display his products well so that he can negotiate them, etc. What ability should the student have? Although this question has several answers, basically, a student must have the ability to learn what he is taught.

As we already know, conductors of electricity, when electrified, acquire electrical charges. Depending on their geometric shape, their dimensions and the environment in which they are found, these conductors may have a greater or lesser capacity to store the electrical charges they receive, or rather, they acquire. Therefore, we can define that:

Electrostatic capacity of a conductor of electricity is associated with its ability to store, for a short time, electrical potential energy.

We call C the electrostatic capacity of the conductor, Q the electric charge it stores and U its electric potential. In this way, we can write:

For a given electrical conductor, if we increase the electrical charge in a directly proportional way, its electrical potential will also increase. In this way, its electrostatic capacity remains constant. In the International System of Units, electric charge is measured in coulomb (C), electric potential is given in volt (V) and electrostatic capacity is given in farad (F).