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Homework Help: How to calculate effective resistance?

  1. Aug 13, 2007 #1
    1. The problem statement, all variables and given/known data
    There are two images:-
    Resistance- Calculate effective resistance between X and Y
    Resistance1- Calculate effective resistance between A and D

    3. The attempt at a solution

    Resistance- I dont think any current passes through the 20 ohm resistor so it seems 10 ohm to me. what do you say?

    Resistance1- is it right??
    =30 ohm???

    Attached Files:

  2. jcsd
  3. Aug 13, 2007 #2
    I don't think you can solve these with ordinary resistance reduction, at least it is too complicated for me to try. I used ohm's law, kirchoff's voltage law and constraints. You know that the if you take any loop that the total voltage is zero, and when all the voltage loops are accounted for you can use linear algebra to solve for the system.
  4. Aug 15, 2007 #3
    I will be glad if you explain to me what you want to convey...
  5. Aug 15, 2007 #4


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    Its simply a wheatstone bridge redrawn ...
  6. Aug 16, 2007 #5
    1.apply superposition theroem
    2.u will egt current and potential difference across the (upper and lower) ,and the (first and last) resistor are the same .
    3 [tex]10 \Omega [/tex]
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