Ohm's law represents a fundamental element to explain certain phenomena related to electricity. More specifically, this law studies the relationship between three concepts: current intensity, potential difference and electrical resistance. In its simplest formulation, this law states that the intensity (called I) flowing through an electrical conductor is directly proportional to the potential difference (V) and, in parallel, inversely proportional to the resistance (R).

### Ohm's law allows to explain the phenomenon of electric current

Electric current involves the passage of electrons from one point to another through a conduit, for example a copper wire. Thus, current intensity refers to the amount of electrons that pass through a conductor during a certain time and its unit of measurement is amperes.

The potential difference, popularly known as voltage or electrical tension, is the force that allows electrons to move through a conductor and its unit of measurement is the volt.

Finally, resistance is the greater or lesser opposition that a certain conductor presents to the passage of electric current (for example, a copper wire is a good conductor of electricity and, therefore, offers little resistance).

### As a consequence of the relationship between these three concepts, its mathematical formulation is as follows: I = V / R

This simple formula explains how voltage, current and resistance are related (intensity is measured in amps, resistance in Ohms and voltage in volts and knowing two of these three data it is possible to obtain the one that is missing).

The discovery of Ohm's Law occurred in the early nineteenth century, a time when the generation of electric current was already known through the investigations of Alexander Volta. The German scientist Georg Simon Ohm (1789-1854) wanted to deepen the advances on the new fluid discovered by Volta and began to experiment on the properties of electricity using metallic bodies until he finally discovered the law that bears his name.

### Ohm's law was definitively perfected by Maxwell's electromagnetic theory

Although Ohm's law was a key contribution to describe how electricity works, it should be noted that this law is not always fulfilled, since Georg Simon Ohm did not consider other laws that do intervene in electricity, Kirchhoff's laws. The set of electrical phenomena were not explained until the scientist James Clerk Maxwell unified electricity and magnetism in the so-called Maxwell's laws.

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