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Why does OHMs law not work on AC circuits?

  1. Feb 20, 2010 #1


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    can someone plz explain to me physically how is it that
    when i have an AC source and i measure Voltage on a resistor its the same with and without the resistor
    and when i have a DC source and i measure Voltage again on the resistor and now theres a different reading

    its like ohm law doesnt support AC circuits but why ?
  2. jcsd
  3. Feb 20, 2010 #2
    Did you use the peak value or the r.m.s. value of the AC source for your computation?
  4. Feb 20, 2010 #3


    Staff: Mentor

    Ohm's law works fine for AC circuits. It sounds like your AC source is closer to ideal.
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