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प्रश्न
What are eddy currents?
उत्तर
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 [after Jean Bernard Léon Foucault (1819-68), French physicist, who first detected them].
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संबंधित प्रश्न
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State applications of eddy currents.
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Eddy currents are also known as ______
A metal plate is getting heated. It can be because ______.
- a direct current is passing through the plate.
- it is placed in a time varying magnetic field.
- it is placed in a space varying magnetic field, but does not vary with time.
- a current (either direct or alternating) is passing through the plate.
Consider a metallic pipe with an inner radius of 1 cm. If a cylindrical bar magnet of radius 0.8 cm is dropped through the pipe, it takes more time to come down than it takes for a similar unmagnetised cylindrical iron bar dropped through the metallic pipe. Explain.
