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Please explain how can this be parrallel?

  1. Sep 13, 2010 #1
    In this circuit, please tell me how they got the 4 ohms and the 12 ohms in parrallel when they look like they are in series


    Please help me i am so desperate for an answer!!!
     

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  3. Sep 14, 2010 #2

    lewando

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    What definition of "parallel" are you using?
     
  4. Sep 14, 2010 #3
    As in resistors are in parrallel and they use the formula 1/Req= 1/R1+....Lewando trust me its very confusing
     
  5. Sep 14, 2010 #4

    lewando

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    I know that circuits can be drawn to confuse intentionally-- the trick is to spot when this is happening. When resistors are "in parallel" they don't need to be drawn both vertically or horizontally-- as in your case they are drawn perpendicularly. But you should realize that you can redraw the circuit so they are literally parallel without changing any functional aspect of the circuit.

    How about this unofficial definition: if there are 2 nodes, A and B with one resistor between them, then you place yet another resistor between them, those two resistors are "in parallel".

    Your example shows exactly that.
     
    Last edited: Sep 14, 2010
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