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Homework Help: Hard circuit problem! help !

  1. May 22, 2010 #1
    hard circuit problem! help plz!

    I need help with question number 4. The problem and relevant equations are attached.
    I= Current flow in Amperes
    V= voltage in volts

    3. The attempt at a solution
    I found the effective resistane (4.4 ohm)
    However, I could not find I3 or V5
    I thought to find I3, all you needed to do is divide the voltage by the single resistor, which woudl give you 2Ameres, however this is not the answer.

    please help/ show me how you did it!! thnks!!!

    Attached Files:

    Last edited: May 22, 2010
  2. jcsd
  3. May 23, 2010 #2


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    Homework Helper

    Re: hard circuit problem! help plz!

    Yes, you would divide voltage across R3 by the resistance. However, we do not know what that voltage is -- it is not 12V, that is the voltage across c & d.

    Try answering these questions to help you get moving on this problem:

    Given the 4.4Ω equivalent resistance, what is the total current in the circuit?
    What is the voltage across R4?
    What is the current through R4?
    Using the total current and current through R4, what would be the current through resistor R5?
    Given the current through R5, what is the voltage across R5?​
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