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Capacitor inductance

  1. Nov 17, 2014 #1
    Can't find an answer to my question. Why do capacitors are so special when it comes to purity, unlike resistors and inductors. I know the capacitor somehow impedes the inductance in the circuit, but how? I just began studying the ac theory, and it boggles my mind.
  2. jcsd
  3. Nov 17, 2014 #2

    Simon Bridge

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    Welcome to PF;
    The capacitor counters an inductance in series with it due to the relationship between changing electric and magnetic fields.
    It is not a simple one, and the theory you are learning now is not the whole story.
    You'll need to be a bit patient.
  4. Nov 17, 2014 #3


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    All components have 'parasitics'. (Try Google on Electronic component parasitics) Indeed, inductors are plagued with self capacitance and many high value inductors will self resonate at low Radio Frequencies (all those coils sitting next to each other with associated capacitance). I think the reason that Capacitors come to mind is that your average circuit has many more capacitors than inductors ('wound components' are expensive to make and tend to be avoided where possible). Even metal film resistors are often made with helical grooves in them which gives them significant inductance at UHF and above. You can buy more expensive resistors that have a longitudinal slot to adjust resistance; much better at high frequencies. Small, chip resistors and capacitors behave pretty well on circuit boards that operate well into the GHz region (look inside your computer).
  5. Nov 17, 2014 #4
    Alright then thank you for the answers.
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