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Homework Help: Determine Resistances in the Circuit

  1. Nov 10, 2007 #1
    A current is driven from a current source as shown attached. Determine the branch currents if the circuit is configured for maximum power transfer.

    Does anyone know how to solve this problem. Any help will be greatly appreciated. Thanks

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    Last edited: Nov 10, 2007
  2. jcsd
  3. Nov 10, 2007 #2


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    YOu just have to replace groups of resistors with a single value.
    Do you know the rules for resitance in series and parallel ?

    Work out the combined resistance of the three in parallel ( 16 60 240 ) and draw them as a single resistor 'A'.
    Then work out the resistance of 'A' and R1 in series - redraw that as a single resistor 'B'
    The you just have the other R16 and B in parallel, work out the resistance of this and then use V = I R
  4. Nov 10, 2007 #3
    Okay, I got the combined resistance of the three in parallel, 12V. How do you continue if you don't know R1. Thanks for your help.
  5. Nov 10, 2007 #4
    I take it that you mean the 3 resistors in parallel amount to 12 Ohms.

    Do you understand the maximum power transfer theorem? It says for max power transfer to occur, the load resistance must match that of the source. Use Thevenin's Theorem to convert the current source to a voltage source. Then you have to choose R1 to match the source resistance.
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