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Homework Help: Why isn't this right? Finding the Va-Vb, kirchofs rule

  1. Oct 27, 2005 #1
    Hello everyone, this seems easy enough...but i missed it!
    Here is the drawing and here is my work:
    http://img203.imageshack.us/img203/3928/lastscan7qe.jpg [Broken]
    In Figure 27-40, the resistances are R1 = 1 , R2 = 2.2 , and the ideal batteries have emfs E1 = 2.0 V, and E2 = 3 = 3 V.

    Fig. 27-40

    (a) What is the current through each battery? (Take upward to be positive.)
    Battery 1: -.328125
    Battery 2: .15625
    Battery 3: .171875
    I found all these and got them right.

    What is the potential difference Va - Vb?
    3.34 <-- wrong

    How did i mess up ? Thanks
    Last edited by a moderator: May 2, 2017
  2. jcsd
  3. Oct 27, 2005 #2
    N/m i got it!!
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