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Homework Help: Basic circuit analysis problem

  1. Oct 7, 2012 #1
    1. The problem statement, all variables and given/known data
    (a) Find v1 and v2 in the following circuit. ( i assume that they are asking for voltage of 30Ω and 5Ω)
    (b) Determine the power dissipated in the 6-Ω resistor.
    https://sphotos-b.xx.fbcdn.net/hphotos-ash3/580277_498142810205239_1717053686_n.jpg [Broken]

    2. Relevant equations
    Equivalent resistor equation.
    Current divider

    3. The attempt at a solution
    simplified the 3 parallel resistors in to Req = 6Ω
    Find Is = 12V/ (12+6+6) = 0.5A
    Back to original circuit, 30Ω || 25+5Ω => Req2 = 15Ω
    Use current divider rule to find Current of eq2 = (10Ω x 0.5A)/(10+15Ω) = 0.2A

    Use that to find I1 = 0.1A and I2=0.1A

    so V1 = 0.1 x 30 = 3V
    V2 = 0.1 x 5 = 0.5V

    P = Is^2 x 6Ω = 1.5W

    THanks for your time.
    Last edited by a moderator: May 6, 2017
  2. jcsd
  3. Oct 7, 2012 #2


    User Avatar

    Staff: Mentor

    All looks right. :smile:
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