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Homework Help: RMS Current HeLp

  1. Feb 27, 2008 #1
    RMS Current...HeLp!!!

    1. The problem statement, all variables and given/known data
    The primary coil of a transformer is connected to a 130 V/60 Hz wall outlet. The secondary coil is connected to a lamp that dissipates 64 W. What is the rms current in the primary coil?


    2. Relevant equations



    3. The attempt at a solution
    I = P/V
    but I don't have P for the primary
     
  2. jcsd
  3. Feb 27, 2008 #2

    rock.freak667

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    Homework Helper

    If the transformer is ideal then the power output is the same as the power input.
     
  4. Feb 28, 2008 #3
    So it is 64W??
     
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