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Inductors v/s resistors in AC circuit.

  1. Feb 23, 2012 #1
    "why are inductors preferred over resistors in reducing current in an AC circuit?"

    The quoted question from a recent exam has caused a little dilemma regarding it's interpretation and answer.

    1) what does 'reduce' refer to?

    2) inductors are preferred as the impedence is dependent on the frequency hence lending flexibility OR they are used because there is almost no power dissipation in the form of heat?

    Do pitch in, with your views.
  2. jcsd
  3. Feb 23, 2012 #2


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    Staff: Mentor

    Yeah, the question is not worded very well. Was there some context given for the question?

    I'd think they are aiming for what you said about lower real power dissipation, but that's only true for AC circuits. Maybe if they were referring to filter circuits, then there are times that inductors would be preferable to resistors (and times when they would not).
  4. Feb 23, 2012 #3


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    Gold Member

    Odd question indeed. Only thing I can guess is maybe it "damps" a bit at start up until you reach steady state. The inductor is also going to shift the current out of phase with the current....that could be good or bad depending on circuit purpose.

    If you have an inductor for the purpose of reducing current....you more than likely have resistance in the circuit as well....turning it into a RL circuit.

    Not sure.....never heard it quite stated like that before.
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