Electricity is a term used in a physics course. Let's analyze the definition of this physical quantity, features of appearance, application.
Definition
What is electricity? A definition in physics implies a combination of different phenomena associated with the movement of an electric charge.
This term was introduced by the English scientist William Gilbert in 1600. He tried to explain the essence of the phenomena that occur when a magnetic compass acts on the body. It was he who in practice confirmed the existence of electrification of bodies.
History Pages
Electricity is a phenomenon that was tried to be explained already during the existence of Ancient Greece. Philosophers who lived in the seventh century BC found out that when amber is rubbed on natural wool, it acquires the ability to attract various objects to itself.
In the seventeenth century, the German Otto von Guericke created an electrostatic machine consisting of a sulfur ball mounted on a metal rod. Such a structure allowed him to observe not only the attraction of objects, but also their repulsion.
Late eighteenth century Englishman Stephen Graya series of experiments was carried out on the transmission of electrical energy over a certain distance. He managed to find out that depending on the composition of the material, the ability to conduct electric current changes.
What is electricity? The concept, the essence of this physical phenomenon was explained by the Frenchman Charles Dufay. In the course of various experiments, he received resin and glass electricity, appearing during friction on silk glass, resin on wool. In the middle of the eighteenth century, Pieter van Muschenbroek developed an electrical capacitor called the Leyden jar. In parallel, experiments concerning the study of atmospheric electricity were carried out by the Russian scientist M. V. Lomonosov.
At the end of the eighteenth century, Coulomb discovered the law according to which electricity is the movement of charged particles.
Early in the nineteenth century, the physicist Oersted discovered the electromagnetic force. He opened and closed the circuit, observing the fluctuations of the compass needle, located near the current conductor. Ampère found that magnetism and electricity are related when there is no static electricity.
Faraday, using the results of the experiments of Ampère and Oersted, discovered the phenomenon of electromagnetic induction. It was he who developed the generator of electrical energy, consisting of a magnetized core, a coil. Electricity passed through it. The meaning of the word after the experiments began to be associated with the movement of charged particles.
Maxwell's work became the crown of all electromagnetic phenomena. In the twentiethcentury, the quantum theory of electrodynamics appeared. She answered all the questions scientists had at that time.
What is electric charge
We have already found out that electricity is a quantity that is associated with the movement of charged particles. What is an electric charge? It implies the ability to create an electric field around the conductor. Bodies that have the same charge repel each other, and bodies that have different charges attract. It is as the particles move that the transfer of electric current occurs inside the conductor.
Natural electricity
Lightning is considered as a bright manifestation of electric current in the living world. Its electrical nature was established in the eighteenth century. It was lightning that caused numerous forest fires. The potential difference that occurs between the layers of the atmosphere and the surface of the Earth is 400 kV.
The processes occurring in the nervous system are also associated with the passage of an electric charge. For example, during an increase in voltage on the cell membrane, a voltage jump is observed, which in biology is considered a nerve impulse. It can be used to transfer information from one cell to another. Fish use electricity to search for prey underwater, as well as to protect themselves from enemies.
For example, the South American electric eel can generate discharges of electricity up to five hundred volts. Lampreys and sharks can useelectricity to detect mining. Special electrical receptors pick up the fields of other organisms.
Conclusion
Experiments with electricity have contributed to technological progress. It is on the basis of electric current that various devices used for everyday human life, in science and technology, function.
To fully meet all the demands that reality puts forward to electricity, powerful current generators have been developed. Their work is based on the theories of electricity and magnetism discussed above.