The electrical conductivity of metals as it is

No one today is surprised that by touching the switch button, we see a light bulb on fire. Often we do not even think that all such actions are based on a whole series of physical phenomena. One of these extremely curious phenomena is the electrical conductivity of metals, which ensures the flow of electric current.

To begin with, probably, it is necessary to be defined, about what generally there is a speech. So, the electrical conductivity is called the ability of a substance to flow electric current. And different substances have this ability to varying degrees. According to the degree of electrical conductivity, substances are divided into conductors, semiconductors and dielectrics.

If we look at the experimental data obtained by the researchers during the study of the electric current, it becomes clear that the conductivity of metals is the highest. This is also confirmed by the daily practice, when metal wires are used to transfer electric current. It is metals that are primarily conductors of electric current. And an explanation for this can be found in the electronic theory of metals.

According to the latter, the conductor is a crystal lattice, the nodes of which occupy atoms. They are located very tightly and are connected with neighboring similar atoms, so they remain practically at the sites of the crystal lattice. What can not be said about electrons located on the outer shells of atoms. These electrons can freely move randomly, forming the so-called "electronic gas". Here is the electronic conductivity of metals and is based on such electrons.

As evidence that the nature of the electric current is due to electrons, we can recall the experience of the German physicist Ricke, set in 1901. He took two copper and one aluminum cylinders with carefully polished ends, put one on top of the other and passed an electric current through them. According to the idea of the experimenter, if the electrical conductivity of metals is due to atoms, then the transfer of matter would occur. However, after the electric current was passed through the year, the mass of the cylinders did not change.

This result led to the conclusion that the electrical conductivity of metals is caused by some particles inherent in all conductors. For this role, the electron, which by that time was already open, was approaching. Later, several witty experiments were carried out, and they all confirmed that the electric current is due to the motion of the electrons.

In accordance with modern ideas about the crystal lattice of metals, its nodes are located ions, and electrons relatively freely move between them. It is a large number of such electrons that ensures high electrical conductivity of metals. In the presence of a small potential difference at the ends of the conductor, these free electrons begin to move, which causes the flow of electric current.

Here it should be noted that the conductivity strongly depends on temperature. Thus, with increasing temperature, the conductivity of metals decreases, and conversely, increases with decreasing temperature, up to the phenomenon of superconductivity. At the same time, it should be remembered that although all metals possess conductivity, its magnitude for each of them is different. The best conductivity of the most widely used and used in the electrical engineering of metals is copper.

So, the given material gives the concept of what the electrical conductivity of metals is, explains the nature of the electric current and explains what it is caused by. A description of the crystal lattice of metals and the influence of some external factors on the conductivity are given.