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Homework Help: Physics Midterm Explanation Kirkoff Rule

  1. May 18, 2009 #1
    Its the part c question....which states

    C) Suppose we made V = 0. Find the new current running through the 5.00 ohm resistor.

    So I just took the biggest loop and did it this way

    Sum of V = 0

    So starting at the upper left hand corner of the circuit

    -3A(15 Ohms) + 50 V + I (5) = 0

    -45 + 50 +5I = 0

    5 +5I = 0
    I = -1 A

    Which is not correct. The answer I think is supposed to be 2.5 Amps but can you tell me what mistake I'm making here.

    Attached Files:

  2. jcsd
  3. May 20, 2009 #2

    Doc Al

    User Avatar

    Staff: Mentor

    I assume the currents labeled in the diagram are from an earlier part of the problem. You can't just assume that the currents remain the same.
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