Grigoriy S. answered • 06/16/22
AP Physics / Math Expert Teacher With 40 Years of Proven Success
During the years 1855 - 1873 James Clerk Maxwell published 4 papers on electricity and magnetism. In 1864 the most important paper "A dynamic theory of of the Electromagnetic Field" was published. In the first part of the paper he introduced Faraday's concept of field. Then he showed that this field (something in space) must store electromagnetic energy and transmit forces, and this medium should obey the laws of dynamics. Maxwell used the math developed by Lagrange to describe the electromagnetic field. The two systems of lines of force (electric and magnetic) he linked by displacement current. Any change in electric force generates magnetic force. The same true in reverse: any change in magnetic force generates electric force. This two-way interaction was the final link in the connection between electricity and magnetism, and it was what gave rise to electromagnetic waves.
He also took account of two fundamental results from experiment: Faraday's finding that an electromotive force is generated in a circuit whenever there is change in the number of magnetic lines of force that pass through it, and Ampere's finding that any loop of electric current acts as a magnet.
Interesting that in 1885 Oliver Heaviside summarized Maxwell's theory of electromagnetism in the 4 now - famous "Maxwell's equations".
