AD 1837

Joseph Henry

Self-Induction

Joseph Henry (AD 1797-1878), an American professor of physics, his discoveries closely paralled those of Michael Faraday. He, too, wondered if magnetism could induce electricity. He, too, designed an electric generator. It did these independently and at almost the same time as Faraday, but even he gave Faraday the credit for these discoveries.

He is, however, given credit for the discovery of self-induction. Self-induction is when a changing magnetic field around a conductor induces an opposing current to the original current in the same conductor. So the magnetic field that is generated by an electric current can induce another electric current that flows in the reverse direction. This second current is considered "self-induced" by the first current.

Fun Word Fact: An Henry is one unit of electrical inductance.

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