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Homework Help: Peak or rms

  1. Feb 2, 2009 #1
    1. The problem statement, all variables and given/known data

    I am confused. My thinking was if a voltage source is given in polar form with the magnitude and angle eg. (10 L0o)then it is Vpk and if only magnitude is given then it is Vrms. Is it right. I am really confused.

    2. Relevant equations

    3. The attempt at a solution

    I know what Vpk and what Vrms mean.
  2. jcsd
  3. Feb 3, 2009 #2
    The way I was taught was that in the frequency domain representation, A∠φ, A is the magnitude of peak value, like you said, and φ is the phase angle or phase shift.

    If you're dealing with steady-state AC circuits and only a magnitude is given, I would think that it would just mean that the phase angle is 0. It may also be written with only a magnitude when dealing with DC circuits. In the books I've used at least, whenever an RMS value was given, it was explicitly stated that it was an RMS value. It may just depend on the conventions used in your particular book. Sorry I don't have a definite answer, but I hope that helps point you in the right direction.
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