This paper describes a pictorial approach to Lenz’s law that involves following four steps and drawing three pictures to determine the direction of the current induced by a changing magnetic flux. Lenz’s law accompanies Faraday’s law, stating that, for a closed conducting loop, the induced emf (electromotive force) created by a changing magnetic flux sets up a current in the loop that tends to oppose the change in flux. Students are often confused by this, but drawing a sequence of three pictures can make it clearer to students how Lenz’s law is applied.
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2018
American Association of Physics Teachers
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