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Determining Peak Current

  1. Nov 18, 2007 #1
    [SOLVED] Determining Peak Current

    1. The problem statement, all variables and given/known data

    A light bulb uses 75 watts of power when a lamp is plugged into a wall socket (RMS voltage = 110 volts alternating at a frequency of 60 hertz)

    Determine the electrical resistance of the light bulb filament.

    Determine the peak current.

    2. Relevant equations

    f = 1/T - I=V/R - P=IV

    3. The attempt at a solution

    I determined the electric resistance to be 161.3 ohms. However, I don't know how to determine the peak current. Can someone please help?
  2. jcsd
  3. Nov 18, 2007 #2
    Someone please help. I know that the answer is 0.96 A.

    I just don't know how to get to this solution and what equation to use.
  4. Nov 18, 2007 #3


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    Homework Helper

    If you know the rms voltage, you can find the peak voltage. What's the relationship between the two? Then from that you can find the peak current since you now know the resistance of the bulb.
  5. Nov 18, 2007 #4
    Okay, I got the answer (actually it is .954 A). Thank you very much.
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