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Motional EMF

  1. Jul 18, 2015 #1
    I understand that EMF is generated by moving a closed loop of wire through a constant magnetic field. I am confused about one thing, who is actually doing work here? (of course it is not magnetic field).
  2. jcsd
  3. Jul 18, 2015 #2
    and one more question. Can EMF be generated through non-constant magnetic field? say, the magnetic field is changing with time.
  4. Jul 18, 2015 #3
    Question 1: You are doing the work by pushing or rotating the coil.
    Q2: Yes. If the magnetic field is changing with time, you don't have to rotate the coil. The changing magnetic flux induces an emf.
  5. Jul 18, 2015 #4


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    yes, that's the way most large generators/alternators work. The magnet is rotated on a shaft inside the surrounding fixed coils

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