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At number 6 in The Guardian’s list of the top ten physicists is Michael Faraday.

 

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Michael Faraday is known both as a physicist and a chemist. In the field of physics the contributions which put him in this list are mainly due to his groundbreaking work on understanding electromagnetism. Amongst other things, he introduced the idea of the electromagnetic field, he discovered the link between magnetism and light, and he discovered electromagnetic induction and invented the first electric motor.

Faraday’s brief biography

Faraday was born in 1791 in Newington Butts which is now part of London, but at the time was in suburban Surrey. He was born into a strictly religious family, his father James was a member of a sect of Christianity known as the Glassites. His family was not wealthy, and Faraday only received a basic education. By the age of 14 he was working as an apprentice bookbinder. It was during his 7 years working as an apprentice bookbinder that Faraday set about educating himself.

At the age of 20, Faraday attended his first lecture given by Humphrey Davy at the Royal Institution. Davy had become one of the foremost chemists of his time, and was a superb lecturer and showman. Faraday was captivated by Davy’s lectures, and wrote copious notes on what he was seeing and hearing in these lectures.

Faraday lovingly collected the lecture notes he had taken, and bound them in a 300-page volume that he sent to Davy, at the same time asking for a job. Davy did not have a job to offer him, but in 1823 Davy suffered an accident in the laboratory, and offered a position to Faraday working as his assistant. This was the beginning of Faraday’s scientific career, and he became one of the best experimentalists physics has seen.

Faraday married Sarah Barnard in 1821, they had met through church. Both were devoutly religious, and his religion influenced Faraday throughout his life. He twice refused the offer to become President of the Royal Society, and also refused the offer of a knighthood. During the Crimean war of 1853-56, Faraday was asked to help develop chemical weapons but refused. In 1848 he was awarded and accepted a “grace and favour” house in Hampton Court, a house which became known as Faraday House. Faraday and his wife had no children, and he died in 1867 at the age of 75. He turned down the offer to be buried at Westminster Abbey, and instead is buried at Highgate Cemetery.

Faraday’s main scientific contributions

The list of Faraday’s contributions to physics is quite long, so I will only mention the highlights. In 1821, hearing about the work which the Danish scientist Hans Christian Ørsted had done on electromagnetism, Faraday and co-workers Davy and William Hyde Wollaston showed that a wire carrying an electric current set up a circular magnetic field about it. Unfortunately, in publishing this work, Faraday failed to mention the contributions of Davy and Wollaston, which strained the relationship between Faraday and his mentor Davy, and led to Faraday being assigned other work for several years, effectively stopping his work on electromagnetism for a period.

In 1831 Faraday conducted a series of experiments which showed the phenomenon of electromagnetic induction. Faraday wrapped two insulated wires around a iron ring, one coil on each side of the ring. Upon passing a current through one coil, he found that a current was produced in the other coil. This is the basis of how transformers work, and was a major breakthrough in our understanding of electromagnetism.

This work showed that a changing electric field produces a magnetic field,and a changing magnetic field produces an electric field. This is now known as Faraday’s law. Faraday went on from this work to produce the first ever electrical dynamo, a device which produces electricity and is the basis of the electric generators today used in power stations.

Later in his life, in the 1860s, Faraday showed that the plane of linearly polarised light could be rotated if the light passed through a magnetic field which was in the same direction as the direction of the light’s travel. This phenomenon, now known as the Faraday effect, was the first indications of a link between light and magnetism, and was a crucial step in Maxwell’s later work which showed that light was just a manifestation of electromagnetism to which our eyes are sensitive.

There is probably no other series of discoveries in the world of Physics which have had more of an influence on our modern everyday lives than those made in the first half of the 1800s in understanding electromagnetism. Almost every device we use today, our entire modern lives, relies on discoveries which were made in large part by Faraday. The unit of capacitance, the Farad, is named in his honour. He is the only physicist in this top ten list who had no formal education, and yet his contributions to our understanding of physics are immense.

Does Faraday deserve his place in this list of the ten best physicists?

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You can read more about Michael Faraday and the other physicists in this “10 best” list in our book 10 Physicists Who Transformed Our Understanding of the UniverseClick here for more details and to read some reviews.

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Ten Physicists Who Transformed Our Understanding of Reality is available now. Follow this link to order

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