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Homework Help: Circuit Analysis

  1. Oct 31, 2009 #1
    I had a simple circuit analysis question and the picture describes everything; I'll restate the questions just in case if you can't read it.

    Find the Req seen from nodes bc, which are the nodes above and below the potential source.
    Find the current, i. That is the current enters the potential source from above.
    Find Vx, that is the V across the 10 ohm resistor that is parallel with the 4 and 6 in the left bottom mesh.

    Let's see who's trading trick or treating with a circuitry problem.

    http://img202.imageshack.us/img202/585/dsc02764n.jpg [Broken]

    http://img202.imageshack.us/img202/585/dsc02764n.th.jpg [Broken]
    Last edited by a moderator: May 4, 2017
  2. jcsd
  3. Oct 31, 2009 #2
    my results were Vx = 20 V
    Req = 2.079 ohms
    i = 4 A

    I'm not sure if they are correct though.
  4. Oct 31, 2009 #3


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    For what it's worth, my answers are the same, except for the current supplied by the voltage source. Really, this is a simple, simple circuit once you get through realizing which branches are in parallel (and simplifying them, of course).

    Note that the voltage source is hooked up between terminals B and C. If you've learned Thevenin's equivalent, you know that you can reduce all the resistances to a black box. If not, note that you found the resistance [itex]R_{BC}[/itex], the resistance seen by anything hooked up between terminals B and C.
  5. Nov 1, 2009 #4
    vx cant be 20 because it's not parallel to the potential source. the value of vx i found was 8.71 and i was 9.61 is this what you came up with?
  6. Nov 1, 2009 #5


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    Oops! I totally misread your response! I got the value of [itex]V_{x}=V_{AC}=11.4 V[/itex] However, I also got the current to be 9.61 A (with some lost numbers as a result of not carrying forward calculations).
    Last edited: Nov 1, 2009
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