Electric current in various media

One of the most important definitions of physics is that an electric current is any ordered movement of particles having any charge. From this it can be concluded that in order for the electric current to appear, it is necessary to have free electrons or ions in the metal, liquid, or some other material, which will move under the influence of the electromagnetic field. At the same time, the electric current in different media will have certain characteristics, because of what its flow in each of them will differ.

If we consider the features of the formation and flow of electric current in metals, then first of all it is worth paying attention to the very structure of metals, which is a crystal lattice. At the same time, ions with a positive charge are located at the nodes of this lattice, and in the space between these nodes, electrons with a negative charge move in a chaotic order. If we create an electric field around the metal, then the motion of the electrons will take a more orderly character. It can be concluded that with respect to metals, the electric current is the directed motion of electrons.

The main characteristic of the flow of electrocurrent in metals is the current-voltage expression, known as Ohm's law. According to this law, the current strength is directly dependent on the voltage and in inverse relationship to the resistance. Analyzing the electric current in various media, it is necessary to give special attention to its formation and flow in a liquid medium.

The electric current in electrolytes arises from a reaction called electrolytic dissociation. Its essence consists in the decomposition of alkali molecules, salts or acids into positive and negative charged ions, which become carriers of the electric charge in liquids. The thing is that when an electromagnetic field starts acting on the solution, the chaotic motion of the ions turns into an ordered one. In this case, positive ions begin to move toward the electrode, which has a negative charge, and negative ions to the electrode having a positive charge. Thus, unlike the same metals, the electric current in the electrolytes is an ordered motion of the ions. In addition, it should be noted that during the passage of these ions through the solution at the electrodes, there is always the formation of substances that are structural components of this solution, be it alkali, acid or salt. This phenomenon, called electrolysis, is actively used in industrial plants for the production of pure metals, as well as for coating and polishing these or other products.

Considering the electric current in various media, in particular, in metals and in liquids, we pointed out that in these substances there are already free ions or electrons. And what happens to the gas, which, as is known, consists of neutral molecules? Electric current without free particles with a negative or positive charge is impossible, so to begin with the gas must be ionized, that is, create charged particles in it. The energy consumed for this will be the ionization energy, which reaches the maximum values for inert gases, and the minimum for alkali metal atoms . The ionization of the gas leads to the formation of three different types of charged particles - negative electrons, plus positive and negative ions. All these particles under the influence of the external field begin to move in an orderly manner, following the same principle as when ions move in liquids. Thus, the electric current in gases is a directed motion of both ions (positive and negative) and electrons.

Drawing the conclusion, we can note the following: the electric current in various media has its own characteristics, which are widely used in various fields of the national economy, as well as in scientific research experiments.