Michael Faraday

His main discoveries include the principles underlying electromagnetic induction,diamagnetism and electrolysis

Although Faraday received little formal education, he was one of the most influential scientists in history. It was by his research on the magnetic field around a conductor carrying a  direct current that Faraday established the basis for the concept of the electromagnetic field in physics. Faraday also established that magnetism could affect  rays of light and that there was an underlying relationship between the two phenomena. He similarly discovered the principles of electromagnetic induction and diamagnetism, and the law of electrolysis His invention of electromagnetic rotary formed the foundation of electric motor technology, and it was largely due to his efforts that electricity became practical for use in technology.

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Courtesy: SciShow