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I The circuit of the induction coil

  1. Dec 20, 2017 #1
    When we turn the circuit off . There will be an induced emf through the coil due to the changing magnetic field of the AC . Therefore V=-L . DI/Dt
    So when the current is zero then the emf has a maximum value . And what about the emf of the source itself ? It's equal to the induced emf? If It has the same value and an opposite direction whey they don't cancel each other out ?
     
  2. jcsd
  3. Dec 20, 2017 #2

    kuruman

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    What circuit? Can you be more specific and describe it, even better can you post it as a figure?
     
  4. Dec 21, 2017 #3
     
  5. Dec 21, 2017 #4

    kuruman

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    OK, I see. The voltmeter cannot detect an instantaneous voltage, which is what you are talking about. You will get a better picture of the instantaneous voltage if you connect an oscilloscope across the induction coil.
     
  6. Dec 21, 2017 #5
    I got it ... So It only detects the voltage between the coil .
    So what I said about the sum of the voltages is right ?
     
  7. Dec 21, 2017 #6

    kuruman

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    According to the Kirchhoff rule, the sum of the voltages around the closed circuit is zero at any time. That is always the case.
     
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