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Michael Faraday (Newington Butts, 22 September 1791 - Hampton Court Palace, Surrey, 25 August 1867), was an English scientist (physicist and chemist) who contributed especially in the fields of electrochemistry and electromagnetism.
Faraday made important contributions to the field of electricity. In 1821, after the Danish chemist Oersted discovered the relationship between electric currents and magnetic fields, Faraday built two devices to produce what he called electromagnetic rotation, in effect an electric motor. Ten years later, in 1831, he began his most famous experiments, with which he discovered electromagnetic induction, experiments that are still the basis of modern electromagnetic technology today. Working with static electricity, he demonstrated that electric charge accumulates on the outside of charged electrical conductors, regardless of what may be inside them. This effect is used in a device called a Faraday cage.
Under Davy's direction he carried out his first researches in the field of chemistry. A study of chlorine led to the discovery of two new chlorides of carbon. He also discovered benzene; he investigated new varieties of optical glass and successfully carried out a series of experiments on the liquefaction of common gases.
He was elected a Fellow of the Royal Society in 1824,[2] appointed Director of the Laboratory in 1825; and in 1833 he was appointed to the "John 'Mad Jack' Fuller" Chair of Chemistry as a life post, without the obligation to lecture. Two years later he was granted a life pension of £300 per annum.
In recognition of his important contributions, the SI unit of electrical capacitance is called the Farad. There was also an older unit of electrical charge called the faraday which was replaced by the coulomb, one faraday being equal to the charge of 6.02 x 1023 electrons (one mole of electrons).
At the age of twenty, in 1812, and on completing his apprenticeship, Faraday attended lectures by the eminent English chemist Humphry Davy, of the Royal Institution and the Royal Society, and by John Tatum, founder of the City Philosophical Society. Faraday's ticket to these lectures was often provided by William Dance (one of the founders of the Royal Philharmonic Society).
Later, Faraday sent Davy a three-hundred-page book based on the notes he had taken in the lectures. Davy's response was immediate, friendly, and favorable. When Davy damaged his eyesight in an accident with nitrogen trichloride, he decided to hire Faraday as his secretary. When John Payne, one of the Royal Institution's assistants, was dismissed, Sir Humphry Davy was tasked with finding a replacement. Davy appointed Faraday as a chemical assistant to the Royal Institution on 1 March 1813.
In the class-conscious British society of the time, Faraday was not considered a gentleman. When Davy made a long trip to the continent between 1813 and 1815, his butler refused to accompany him. Faraday joined him as Davy's scientific assistant, and was required to act as butler until a replacement could be found in Paris. In fact, Faraday acted as butler throughout the trip. Davy's wife, Jane Apreece, refused to treat Faraday as an equal (making him travel outside the carriage, eat with the servants, etc.) and made him feel so unhappy that he even considered returning to England alone and abandoning science. However, the trip gave him access to the European scientific elite and a wealth of stimulating ideas.
Faraday was a devout Christian and a member of the small Glasite group, a branch of the Church of Scotland. He would later serve twice as dean of the church they had at Glovers Hall, Barbican, which would later be moved to Barnsbury, Islington.
He married Sarah Barnard (1800–1879) on 2 June 1821, and they had no children.[2] They met while attending services at the Sandemanian church.
Faraday worked in the world of chemistry, electricity, magnetism and diamagnetism.
He created the Faraday cage, in his work on static electricity, Faraday demonstrated that charge resides only on the outside of a charged conductor, and that the external charge has no influence on anything enclosed within a conductor. This is because the external charges redistribute themselves in such a way that the internal fields due to them cancel out. This shielding effect is now known as the Faraday cage.
Faraday was an excellent experimentalist who conveyed his ideas in simple and clear language. However, his mathematical abilities did not go beyond trigonometry or the simplest algebra. It was James Clerk Maxwell who, starting from the work of Faraday and others, and consolidating them into a set of equations, laid the foundation for modern theories of all electromagnetic phenomena. Maxwell wrote that Faraday, with his use of field lines, "had indeed been a mathematician of the first order—from whom mathematicians of the future might derive valuable and fertile methods."
