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Homework Help: Need your help with parallel circuits

  1. Jan 7, 2006 #1
    I need to work out the total resistance of a heating element made up of 3 strips of resistive material in paralell. We are told that the unit is 12V and theheat is generated at a rate of 40W, I need to calculate the total resistance of the element. I kno I have to use the formular R=v²/r where R is the resistance, V is the voltage and r is the power(watts). i know that the voltage will be the same across all the strips but will the power, could you help me please?
  2. jcsd
  3. Jan 7, 2006 #2


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    The power consumed is porportional to the total circiut resistance.

    Thiis is a pretty straight forward problem, don't over think it.
  4. Jan 7, 2006 #3


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    Start by drawing off the circuit, that'll help.
  5. Jan 7, 2006 #4

    what is the problem here?
  6. Jan 7, 2006 #5
    Inversely propotional.
  7. Jan 8, 2006 #6
    thanks for your help guys
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