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Finding the voltage after current was found

  1. Nov 17, 2015 #1
    1. The problem statement, all variables and given/known data
    Find ##v_0##
    vVfyzql.png
    2. Relevant equations
    looking for which way is the best

    3. The attempt at a solution
    Using parallel and series resistor I have found that ##i=0.006 A## what should I do next?
     
  2. jcsd
  3. Nov 17, 2015 #2

    SammyS

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    What is the voltage drop across R1 ?

    Added in Edit:
    By the way: That current looks suspiciously low.
     
  4. Nov 17, 2015 #3

    gneill

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    If you have i then you can find the potential drop across R1. Go from there.

    Personally I'd probably have taken a different approach and transformed the source voltage and R1 into a Norton equivalent, absorbing R3 into it, then convert back to Thevenin and swallow up R4 too. That would leave a simple voltage divider at the end.
     
  5. Nov 17, 2015 #4
    What I did is:
    ##180+60=240## than ##\frac{240*80}{240+80}=60## and than ##60+20=80k\Omega##
     
  6. Nov 17, 2015 #5

    gneill

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    Yes, that's fine.
     
  7. Nov 17, 2015 #6
    So I found that the voltage on ##R_1=120## so I have ##480-120=360## finding the current on ##R_{4+2}## is ##0.0015A## so the voltage on ##R_4## is ##90## and overall it is ##360-90=270##?
     
  8. Nov 17, 2015 #7

    gneill

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    That works.
     
  9. Nov 17, 2015 #8

    ehild

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    Correct!
     
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