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Michael Faraday (1791-1867) was a British scientist who contributed to the field of electromagnetism and invented the Bunsen burner.
Michael Faraday was born on September 22, 1791, near Elephant and Castle, London. At fourteen he apprenticed as a book-binder and during his seven year apprenticeship developed an interest in science.
After he sent Humphry Davy a sample of notes that he had made, Davy employed Faraday as his assistant. In a class-ridden society, he was not considered to be a gentleman, and it is said that Davy's wife refused to treat him as an equal and would not associate with him socially.
His greatest work was with electricity. In 1821, soon after the Danish chemist, Ørsted, discovered the phenomenon of electromagnetism, Faraday built two devices to produce what he called electromagnetic rotation: that is a continuous circular motion from the circular magnetic force around a wire. The electric generator used a magnet to generate electricity. These experiments and inventions form the foundation of modern electromagnetic technology
Ten years later, in 1831, he began his great series of experiments in which he discovered electromagnetic induction. His demonstrations exposed the concept that electric current produced magnetism. Faraday proposed that electromagnetic forces extended into the vacinity around the conductor, but did not complete his work over this proposal. Faraday's experimental visualization, of lines of flux emanating from charged bodies, was mathematically modelled by James Clerk Maxwell, which has evolved into the generalization known as field theory.
In 1845 he discovered what is now called the Faraday Effect. The plane of polarization of linearly polarized light propagated through a material medium can be rotated by the application of an external magnetic field in the propagation direction. He wrote in his notebook, "I have magnetized a beam of light". This was one of the earliest demonstrations of the relationship between electromagnetism and light.
In the work on static electricity, Faraday demonstrated that the charge only resided on the exterior of a charged conductor, and exterior charge had no influence on anything enclosed within a conductor; this shielding effect is used in what is now known as a Faraday cage.
He gave a successful series of lectures on the chemistry and physics of flames at the Royal Institution, entitled `The Natural History of a candle'; this was the origin of the Christmas lectures for young people that are still given there every year.
The unit of capacitance, the farad is named after him; his picture has been printed on British £20 banknotes.
Faraday's sponsor and mentor was John 'Mad Jack' Fuller, who created the Fullerian Professorship of Chemistry at the Royal Institution. Faraday was the first, and most famous, holder of this position to which he was appointed for life.