electromagnetism summary

Learn about the three landmark discoveries in the field of electromagnetism

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Below is the article summary. For the full article, see electromagnetism.

electric fieldFigure 1: Electric fields. (Left) Field of a positive electric charge and (right) field of a negative electric charge.

electromagnetism, Branch of physics that deals with the relationship between electricity and magnetism. Their merger into one concept is tied to three historical events. Hans C. Orsted’s accidental discovery in 1820 that magnetic fields are produced by electric currents spurred efforts to prove that magnetic fields can induce currents. Michael Faraday showed in 1831 that a changing magnetic field can induce a current in a circuit, and James Clerk Maxwell predicted that a changing electric field has an associated magnetic field. The technological revolution attributed to the development of electric power and modern communications can be traced to these three landmarks.

André-Marie Ampère Summary

André-Marie Ampère was a French physicist who founded and named the science of electrodynamics, now known as electromagnetism. His name endures in everyday life in the ampere, the unit for measuring electric current. Ampère, who was born into a prosperous bourgeois family during the height of the

J.J. Thomson Summary

J.J. Thomson was an English physicist who helped revolutionize the knowledge of atomic structure by his discovery of the electron (1897). He received the Nobel Prize for Physics in 1906 and was knighted in 1908. Thomson was the son of a bookseller in a suburb of Manchester. When he was only 14, he

Carl Friedrich Gauss Summary

Carl Friedrich Gauss was a German mathematician, generally regarded as one of the greatest mathematicians of all time for his contributions to number theory, geometry, probability theory, geodesy, planetary astronomy, the theory of functions, and potential theory (including electromagnetism). Gauss

James Clerk Maxwell Summary

James Clerk Maxwell was a Scottish physicist best known for his formulation of electromagnetic theory. He is regarded by most modern physicists as the scientist of the 19th century who had the greatest influence on 20th-century physics, and he is ranked with Sir Isaac Newton and Albert Einstein for