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AC Circuits question verification

  1. Sep 5, 2012 #1
    Hi there,

    in this youtube tutorial about AC circuits


    at about 4:08 It's supposed to be z=√(R^2+(XL-Xc)^2)) but in the example she does Xc-XL, is there a reason for this or is it a mistake in her working??
  2. jcsd
  3. Sep 5, 2012 #2
    Xl - Xc is correct. In her example she has (Xc - Xl)^2. When she squares the difference, the result is the same.
  4. Sep 5, 2012 #3
    The equation should be written
    Z = √(R^2 +(XL ~XC)^2)
    because it is the difference between XL and XC that is important. It does not matter which is greater.
  5. Sep 8, 2012 #4
    In this equation that's true but generally Xl is regarded as positive and Xc as negative.
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