We explain what alternating current is and how it works. Also, examples and the difference between alternating and direct current.
Alternating current is a type of electrical current whose behavior is fluctuating.
What is AC?
The type of alternating current (AC) is calledelectric current more used domestically, characterized by oscillating in a regular and cyclical way in its magnitude and sense. The most common way to represent it is by means of a graph (on an x / y axis) in the form of sinusoidal waves.
All electric current is the flow of electrons throughout the molecular structure of a conductive material, always from the positive pole to the negative pole of the material (these poles are assigned in a totally conventional way).
This phenomenon, known since human antiquity, is due to the presence of free electrons in the last layer of the atoms of these materials, which, since they are not very strongly bound to the atomic nucleus, can migrate to the atom next, thus generating a current. This is what happens, for example, when rubbing certain materials.
For its part, alternating current was discovered by the Serbian physicist, engineer, and inventor Nikola Tesla in 1882, the date on which he designed and built the first motor to use it for its operation.
The genius of this engineer is also due to the system currently used for the transformation and distribution of this current, whose first emission occurred in 1891 in Colorado, United States, thus initiating the so-called War of the Currents between Tesla himself and Thomas. Edison, who despite the obvious advantages of alternating current defended the use of direct current (DC) as he owned most of the industrial patents of the latter.
Examples of alternating current
Cars use alternators taking advantage of direct current from batteries.
Alternating current is the most used in our life. It is generated in various ways, in power plants (hydroelectric, wind, nuclear, etc.) and through the use of alternators (such as those in automobiles), which take advantage of direct current from batteries and other accumulators, to generate alternating current by magnetic induction (continuous polarity changes in the electric field conductive material).
Difference between alternating and direct current
The electrical flow of direct current is stable, unidirectional and unchanged.
The main difference between alternating and direct current has to do with the properties of electrical flow: in the case of direct current the flow is stable, unidirectional and invariable (it is represented on an x / y axis as a straight line) ; While alternating current oscillates in its magnitude and polarity in a cyclical manner (it is represented as sinusoidal waves on an x / y axis).
This, however, results in a number of different features. Alternating current is much easier to transform than direct current, since to raise the voltage of the latter requires a series of dynamos connected in series, which is not very practical, while with alternating current it can be done simply by means of a transformer.