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Ap physics b circuits problem

  1. Feb 25, 2010 #1
    ok there is a picture that goes along with it, i will try and draw it in as best i can.
    We've got a 12 volt battery. a 4 ohm resistor is in series with this big thing im going to describe next. A two ohm and 1 ohm resistor that are in series are in parallel with a 5 ohm and 1 ohm resistor that are also in series. What is the power dissipated in the 5 ohm resistor?

    l l
    l l

    i doubt that will come out okay but w/e
  2. jcsd
  3. Feb 25, 2010 #2
    dang it..
  4. Feb 25, 2010 #3


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    Gold Member

    You need to find the currents and voltages of the circuit. Just keep simplifying the circuit by combining series and parallel resistances into effective resistances. Once you find the total effective resistance seen by the load, you can find the total current. This current, by Kirchoff's Current Law, must be split up between the parallel branches that you have. So you then need to know the voltage drop across the branches to find the currents in the individual branches. Once you have the current in the 5 Ohm branch, you can find the power.
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