What is electricity?

Electricity is a natural phenomenon. Electricity is a property that produces repulsion and attraction between subatomic particles such as electrons and protons. It is one of the four basic interactions in nature. There are two kinds of electricity or charges: we call one positive and the other negative. Through experiments, we found that charged objects repel each other when the polarity is the same, attract each other when the polarity is opposite, and the attraction or repulsion obeys Coulomb's law. The discharge phenomenon in nature The unit of charge in the International System of Units is Coulomb. It is found that in ancient times, in China, the ancients thought that the phenomenon of electricity was caused by the excitation of Yin and Yang, and Shuo Wen Jie Zi said that "electricity, Yin and Yang excite brilliance, and it is from rain to charity". "Vocabulary" includes "thunder from behind, electricity from application. Yin and yang become thin and become thunder, and discharge becomes electricity. " There is a record about static electricity in Lun Heng (about the first century AD, that is, the Eastern Han Dynasty). When amber or tortoise shell is rubbed, it can attract light and small objects, and it also describes the phenomenon that silk is rubbed to generate electricity. However, ancient China didn't know much about electricity. Around 600 BC, the Greek philosopher Thales (640-546 BC) knew that the friction of amber would attract fluff or sawdust, which is called static electricity. Electricity in English means "amber" in ancient Greek. Elektron's Modern Exploration in Greece18th century, the West began to explore various phenomena of electricity. American scientist Benjamin Franklin (1706 ~ 1790) thinks that electricity is a weightless fluid and exists in all objects. When an object gets more electricity than normal, it is called positively charged; If it is less than a positive constant, it is called negatively charged. The so-called "discharge" is the process from positive current to negative current. This theory is not completely correct, but it retains the names of positive charge and negative charge. The concept of "electricity" in this period is a material proposition. Franklin did many experiments and put forward the concept of current for the first time. 1752, in a kite experiment, he put a kite with a key in the cloud with a metal wire, and the metal wire wet by rain led lightning in the air between his finger and the key, which proved that lightning in the air and electricity on the ground are the same thing. From matter to electric field, electricity began to develop in18th century. 1767 J.B.Priestley and C. A. Coulomb (1736-1806) discovered the law that the force between electrostatic charges is inversely proportional to the distance. /kloc-in 0/800, Italian Volt (A.Voult) made the first battery by immersing copper and tin in salt water and connecting wires. It provided the first continuous power supply and was called the ancestor of modern batteries. 183 1 year, M. Faraday of Britain demonstrated the generation of induced current by using the change of magnetic field effect. In 185 1, he put forward the concept of physical power line. This is the first time to emphasize the concept of charge transfer to electric field. Electric field and magnetic field 1865, Maxwell put forward the mathematical formula of electromagnetic field theory and provided the concept of displacement current. The change of magnetic field can produce electric field, and the change of electric field can produce magnetic field. Maxwell predicted the existence of electromagnetic radiation, and such electromagnetic waves were shown in H.Hertz of 1887. As a result, Maxwell integrated electricity and magnetism into a theory, which also proved that light is an electromagnetic wave. The development of Maxwell's electromagnetic theory also explains microscopic phenomena, pointing out the existence of split charges rather than continuity. 1895, H.A. Lorenz assumed that these split charges were electrons, and the role of electrons was determined by the electromagnetic field of Maxwell's electromagnetic equation. 1897, J.J.Thomson of Britain confirmed that the electronicity of these electrons is negatively charged. 1898, W.Wien observed the deflection of anode rays and found the existence of positively charged particles. From particles to quantum, human beings have always described the world of "electricity" with particles and waves existing in nature. /kloc-in the 0/9th century, the appearance of quantum theory put the originally constructed particle world to the test again. Werner Heisenberg's "uncertainty principle" holds that the velocity and position of a particle cannot be measured at the same time; Electrons are no longer countable particles; Nor does it run in a fixed orbit. 1923, Louis Blay proposed that tiny particles have both particle property and fluctuation when they move, which is called "mass-wave duality", while Erwin Schrodinger used mathematical methods to describe the behavior of electrons with functions, and obtained the probability distribution of electrons in space with wave mechanics model. According to Heisenberg's uncertainty principle, we can't measure accurately. In niels bohr's hydrogen atom model, the electron movement radius of the ground state atom is the position with the largest probability of electron occurrence in the wave mechanics model. With the development of science, people gradually understand that the values obtained by the physical quantity of electricity are discontinuous and the laws they reflect are statistical.