(22 September 1791 – 25 August 1867)
Faraday was one of the greatest scientific discoverers of all time. His main contributions were in the fields of electromagnetism and electrochemistry. In a 2002 survey in UK, Faraday was ranked 22nd in the BBC’s list of the 100 great Britons. In fact, Einstein kept Faraday’s photo on his office wall, along with the photos of Newton and Maxwell.
Faraday was born in 1791 in Surrey, England. Since his family was poor, he got only the most basic education and he had to start working at the age of thirteen with a bookbinder. Here he read most of the books he bound. Also, he attended the lectures of a great chemist called Humphry Davy.
Faraday sent Davy a 300-page book containing the notes he took of his lectures. This impressed Davy and he soon appointed Faraday as his assistant. When Davy went on a long tour of Europe, he took Faraday along with him as an assistant. Thus, Faraday got to meet great scientists like Ampere in Paris and Volta in Milan.
In 1816, aged 24, he gave his first ever lecture, on the properties of matter, to the City Philosophical Society, and he published his first academic paper, discussing his analysis of calcium hydroxide, in the Quarterly Journal of Science.
In 1821, aged 29, he was promoted to be Superintendent of House and Laboratory of the Royal Institution. Faraday married Sarah Barnard in 1821. They met through their families at a church. They were to have no children.
At 32, he was elected to the Royal Society and at 33, he became the Director of the Royal Institution’s Laboratory. At 41, he was made the Fullerian Professor of Chemistry at the Royal Institution of Great Britain, a position he held for the rest of his life. In his fifties, he was twice offered the Presidency of the Royal Society, but he turned it down. He suffered a nervous breakdown in 1839 but eventually returned to his scientific investigations.
Faraday discovered two new compounds of chlorine and carbon. He showed that ammonia could be liquefied under pressure, and then evaporated to cause cooling, which led to commercial refrigeration. He also invented an early form of what was to become the Bunsen burner.
Faraday was also responsible for discovering the laws of electrolysis. These findings led Faraday to a new theory of electrochemistry. Electrochemistry is the science that has produced the lithium ion batteries and metal hydride batteries capable of powering modern mobile technology. He also popularized terminology such as anode, cathode, electrode, and ion.
Faraday discovered that a magnetic field produces an electric current. This principle of induction made possible the dynamo, or generator. Faraday discovered that many materials exhibit a weak repulsion from a magnetic field: a phenomenon he termed diamagnetism. Faraday discovered that an intense magnetic field can rotate the plane of polarized light. This is now termed the Faraday effect. Also, Faraday cage is named after him because he demonstrated that in such a cage the electric charge resides on the outside and the inside of the cage is free from electric charge.
Faraday was thus an excellent experimentalist but his mathematical abilities, however, did not extend as far as trigonometry or any but the simplest algebra. He knew little of higher mathematics such as calculus. It was left to James Clerk Maxwell to take the work of Faraday, and others, and consolidate them with a set of equations that form the basis of all modern theories regarding electromagnetic phenomena.
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