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Find Thevenin equivalent circuit

  1. Feb 9, 2013 #1
    1. The problem statement, all variables and given/known data

    Find Thevenin equivalent circuit as seen across terminals A and B for each circuit.

    2. Relevant equations


    3. The attempt at a solution

    Those resistors are in parallel because not all of the current going through the top one is going to go through the next one, right?
    So I add the resistors to make an equivalent resistance, but I'm not sure what to do after that.

    I need to find the open-circuit voltage, but I don't know how to do that mathematically.

    And I need to find the short circuit current, which is [tex]I=\frac{V_T}{R_T}[/tex].

    Is the [tex]V_T[/tex] just the voltage source? And is the [tex]R_T[/tex] just the equivalent resistance that I found?


    Attached Files:

  2. jcsd
  3. Feb 9, 2013 #2

    rude man

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    See above.
  4. Feb 10, 2013 #3
    What do you mean by wrong argument? That's not the reason they're in parallel? There's a different reason they're in parallel? Or are they not in parallel at all?

    The open circuit voltage would be [tex]V_{Th}=\frac{(2)(100)}{100+100}=1[/tex] right?

    And the short circuit current would just ignore the middle resistor and that would be [tex]I=\frac{2}{100}=0.04A[/tex] right?

    Ok so [tex]R_{Th}=\frac{1}{0.04}=25[/tex]

    So to answer the question posed, I would make a circuit replacing the [tex]V_{in}[/tex] with [tex]1V[/tex] and replace the two resistors with a 25 Ohm resistor?

    Thanks for the response.
    Last edited: Feb 10, 2013
  5. Feb 10, 2013 #4

    rude man

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    See above.
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