Immediately after the discovery of the potential difference and the movement of electrons (current) caused by it, natural scientists tried to understand how these two electrical quantities are related. For many years, neither the Italians L. Galvani and A. Volta, nor the French researcher Ampere, since the data collected by that time was insufficient. And only in the 19th century, a naturalist from Germany, Georg Ohm, managed to establish a connection between the current strength in the circuit under study and the voltage acting on its terminals.
Ohm's opening
The great scientist argued that these two quantities are linearly related with a certain coefficient, depending on the properties and characteristics of the circuit (conductor) under investigation. This coefficient will later be defined as the resistance of the chain, and the unit of its measurement will be called Ohm (in honor of the naturalist). The scientist came to this discovery after conducting a number of experiments, from which it followed:
- different substances conduct current in different ways, and some of them do not pass it at all;
- the closer the material approaches metals in its properties, the better its conductivity;
- with increasing voltage, the current in conductors made of the same material increases proportionally.
Later, Ohm's law served as the basis for the development of an entire branch of industry called "electrical engineering".
Regulatory documents based on Ohm's law
Further development of technical thought led to the fact that in the 20th century, structures were developed and appeared, to which Ohm's law was directly related. In the conditions of industrial production, a regulatory framework was developed that regulates the main parameters of electrical circuits and structural elements (their resistance to current, in particular).
So, in PUE-7 clause 1.8.40 the conditions for measuring leaks of cable lines (permissible conductivity of their protective sheath) are determined. And in PTEEP clause 2.7 the resistance of the grounding elements of industrial and household electrical installations and circuits is normalized (a photo of the grounding circuit is given below).
In addition, these values are regulated in other regulatory documents (in GOST R 57190-2016, eg).
The last stage of G. Ohm's research
His further research on issues related to electricity was associated with the unipolar conductivity of metals (1830) and the study of the phenomenon of heating wires with current (1829).
Additional Information: In the 40s, the scientist took up the problems of acoustics, which led to results of great importance.
In conclusion, we note that Ohm's discovery made it possible for the first time to look at the manifestations of electric current from a quantitative perspective. It can be classified as fundamental in terms of the development of scientific knowledge. Moreover, all subsequent theoretical calculations and experiments have convincingly proved the complete correctness of the great scientist.
Subsequently, this statement began to be interpreted as a law of nature, equal in significance to the discovery of universal gravitation by I. Newton.