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Resonance in EM?

  1. May 12, 2010 #1
    Hi everyone,

    I've dealt with resonance (normal modes of a system) in a fair amount of detail, but it was in the context of a mechanics course. Now, I'm trying to extent this concept to electromagnetism, particularly LRC circuits, and I'm having a really hard time wrapping my head around it. I can't understand "what" is resonating, and the mechanism behind why it resonates. This area of physics has never been a strong point for me.

    Can anyone either provide a brief crash course or recommend any good books or websites that can explain this to me?
  2. jcsd
  3. May 12, 2010 #2
    Once you understand electrical impedance you are pretty much done.

    There are a lot of books which solve the rcl circuit. The main idea is the the capacitor doesn't want to lose its voltage and the coil wants to keep its current. Because the voltage of the capacitor stays up the current grows to be pretty high. When the capacitor is finally empty the capacitor would be ready to stop the current, but the coil wants to keep the current running and pushes all the charge to the other side of the capacitor. Once the coil is done pumping current the capacitor is charged and the whole thing restarts.
  4. May 13, 2010 #3
    "The Feynman Lectures on Physics", V2, Chap. 23 ("Cavity Resonators") might be helpful.
  5. May 14, 2010 #4
    Thanks to the both of you. I signed out Feynman's lectures today and skimmed a bit of it. It's exactly what I needed to know.
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