Voltage division question

Discussion in 'Homework Help' started by Henry Jyrkinson, Feb 17, 2015.

  1. Henry Jyrkinson

    Thread Starter New Member

    Feb 17, 2015
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    Hi here is my problem

    voltagedivision.png
    So I need to solve Vout.
     
  2. shteii01

    AAC Fanatic!

    Feb 19, 2010
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    Are R1 and R4 in parallel?
     
  3. Henry Jyrkinson

    Thread Starter New Member

    Feb 17, 2015
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    Yes they are.
     
  4. MikeML

    AAC Fanatic!

    Oct 2, 2009
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    Write a KCL equation for the current in/out of node(Vout).
     
  5. crutschow

    Expert

    Mar 14, 2008
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    You can also convert each parallel pair of resistors to the equivalent single resistance and solve the voltage from that.
     
  6. WBahn

    Moderator

    Mar 31, 2012
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    There's only one pair of resistors in parallel.
     
  7. crutschow

    Expert

    Mar 14, 2008
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    The op stated that R1 and R4 are in parallel.
     
  8. WBahn

    Moderator

    Mar 31, 2012
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    Yes. R1 and R4 are in parallel. Those are the ONLY two that are in parallel.

    R2 and R3 are NOT.
     
  9. crutschow

    Expert

    Mar 14, 2008
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    You are correct of course. Silly me, as you might have guessed, I didn't closely look at what I thought were two ground symbols. :oops:
     
  10. WBahn

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    Mar 31, 2012
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    We've all done it. And we will all do it again. And again.
     
  11. Dodgydave

    Distinguished Member

    Jun 22, 2012
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    Work out the parallel resistance, (20K) then remove the resistor to ground (R3),and work out the current across the 90V supply, then work out the voltdrop across R2, subtract the 30V and that should be it...
     
  12. WBahn

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    Mar 31, 2012
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    On what basis are you removing R3?
     
  13. JoeJester

    AAC Fanatic!

    Apr 26, 2005
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    I'm sure glad Henry Jyrkinson will get a good grade after all the work he's done to solve this problem.
     
  14. WBahn

    Moderator

    Mar 31, 2012
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    Well, I guess we can give credit where credit is due -- he DID come back and answer one of the clarification questions that was asked. That's better than most!

    He's also had to deal with some false hints, which can be frustrating but also very educational.

    Still, I'm with you -- need to see some effort from him if there is much point going any further.
     
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