Previously, we have made a brief review of the development process of electromagnetic theory, in which the masters who have made outstanding contributions to this field have also made a key description. Now we're going to spend a whole article introducing a God-like character. Strictly speaking, he is not a theorist, but his application of electromagnetism can be described as the peak, and he is a figure who cannot be avoided when it comes to the field of electromagnetism. He was not as famous as many scientists, but his contribution was like divine help, and all mankind still enjoys the gospel he has given. But he is little known, and his name is rarely mentioned in various textbooks. This may also be one of the purposes of writing this article.

Nikola Tesla (1856-1943) is a Serbian-American inventor, mechanical engineer and electrical engineer. On July 10, 1856, Tesla was born in the village of Smewan, Croatia. Tesla went to school in Karlovac, Croatia as a teenager, and studied physics, mathematics and mechanics at Graz University of Technology in Austria in 1875. He only attended the university for one year. The next year, the Military Border Agency was canceled. He lost his scholarship and was forced to withdraw because he could not afford the tuition. Tesla did not graduate. In 1877, Tesla went to Prague to study for two years. He attended the university and studied in the library. In 1879 he tried unsuccessfully to find a job in Maribor and returned to Prague to continue his studies until he was 24. In the autumn of 1882, Tesla worked as an engineer in the Paris branch of the Edison Telephone Company and successfully designed the first induction motor model. In 1884, he went to the United States to work in the Edison Laboratory, and remained in the United States and became an American citizen. In 1884, Tesla first set foot on American soil, came to New York, began to work in the Edison laboratory.

In 1885, about a year after Tesla left Edison, he founded his own company. Before and after he invented too many things, until his death, a total of more than 1000 patents. Among Tesla's many inventions, the most beneficial to the public is its invention of various AC motors, and its invention of multi-phase current and multi-phase power transmission technology in 1885. Since then, alternating current has replaced direct current as the mainstream of power supply. Tesla, on the other hand, had to pay $2.5 in royalties for every horsepower of AC sold at the time. Driven by powerful interests, a consortium force at the time threatened Tesla to give up the patent and intended to monopolize it for profit. After much negotiation, Tesla decided to give up the patent of AC power, and he tore up the patent of AC power and lost the right to collect royalties. Since then, AC has no patent and has become a free invention. If the invention patent of alternating current is not given to all mankind for free use, each horsepower alternating current will bring him a "patent fee" of $2.5, and he will be the richest person in the world. After polyphase alternating current, he went on to study rotating magnetic fields. From 1892 to 1894, Tesla served as vice president of the American Institute of Electrical Engineers and a pioneer of the American Institute of Radio Engineers, later known as the Institute of Electrical and Electronics Engineers. From 1893 to 1895, he studied high-frequency alternating current. He used a conical Tesla coil to create a million-volt alternating current, he studied the "skin effect" in conductors, designed a tuned circuit, invented the cordless gas discharge lamp, and proposed the wireless transmission of electrical energy Possibility, built the first radio transmitter. Many materials show that the inventor of radio is not Marconi. In 1893, Tesla first publicly demonstrated radio communication in St. Louis, Missouri. And in 1897 in the United States obtained a patent for radio technology. However, the U.S. Patent Office revoked its patent in 1904 and instead granted Marconi a patent for his invention of radio. This move may be the result of the influence of Marconi's economic backers in the United States, including Thomas Edison and Andrew Carnegie. In 1917, Tesla proposed the principle of radar to the U.S. Navy, which was later shelved by Edison. The first discovery of X-rays also led to the development of a number of experiments to produce X-rays. Tesla believed that the energy of X-rays that could be generated by his circuit was much greater than that of ordinary instruments. He also talked about the hazards of working with his circuit and single-node X-ray generating equipment, and sent some of the experimental data he had completed, including taking X-ray photos of his hands, to Roentgen, which he had not published. He holds a patent for the invention of the transistor, and used the transistor to successfully receive radio waves from outer space for the first time. When he designed the Niagara hydroelectric plant in his thirties, the CCP used his nine patented inventions, including Tesla's invention of an alternating current generator and alternating current transmission technology.

This is Nikola Tesla, his life is very legendary, there are many rumors and unsolved mysteries about him. The Tunguska explosion is suspected to be related to him. Many data show that this is caused by one of his experiments, which has not been confirmed so far. There are also rumors that he also uses the resonance principle, uses the earth's natural frequency to create artificial earthquakes, tsunamis, studies the anti-gravity principle to create flying saucers, and so on. What's more, he uses electricity and magnetism to distort or change space and time for space transmission and time travel. These inventions and discoveries beyond the time of science and technology several times, some theories even today's science and technology can not be a perfect answer. After Tesla's death, the U.S. FBI confiscated all his design drawings and experimental works, and the U.S. military's research on his thesis has not stopped. This also creates a mystery for Tesla.

We may not be able to judge that all of Tesla's inventions or discoveries are true for various reasons. Even so, as long as one or two of the more than 1000 patents in his life are true, he cannot be erased for all mankind. Contribution. It is also to commemorate this figure who has made great contributions in the field of electromagnetic applications. In 1960, the International Electrotechnical Commission in Munich identified Tesla as the international scientific unit of magnetic induction.