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State applications of eddy currents.

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State applications of eddy currents.

Write two applications of eddy current.

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Solution

  1. Dead-beat galvanometer: The coil is wound on a light aluminium frame in a pivoting moving-coil galvanometer for measuring current. The coil is swiftly brought to rest by the rotation of the metal frame in the magnetic field, which causes eddy currents in the frame that oppose the rotation. This causes the galvanometer to stop working.
  2. Electric brakes: When a conducting plate is pushed into or pulled out of a magnetic field fast, the interaction between the moving conductor’s eddy currents and the field slows down the velocity. This property of eddy currents is used in vehicles as a method of braking.
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Chapter 12: Electromagnetic induction - Exercises [Page 286]

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