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What are eddy currents? - Physics

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Question

What are eddy currents?

Short Answer
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Solution

Whenever a conductor or a part of it is moved in a magnetic field, “cutting” magnetic field lines, or placed in a changing magnetic field, the free electrons in the bulk of the metal start circulating in closed paths equivalent to current-carrying loops. These loop currents resemble eddies in a fluid stream and are hence called eddy or Foucault currents.

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Chapter 12: Electromagnetic induction - Exercises [Page 286]

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