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Homework Help: Steady State Sinusoidal using Nodal Analysis

  1. Mar 21, 2015 #1
    1. The problem statement, all variables and given/known data
    problem 47.jpg

    The photo included provides the problem but the professor stated that the right side source is supposed to be 100t and not 80t. The problem wasn't printed correctly in the book so I assume the solution wasn't either. The solution via the book is v1=2.56cos(100t+139.2°), v2=4.35cos(100t+138.3°)

    2. Relevant equations
    Rectangular to Polar Notation
    Polar to Rectangular Notation
    Ohms Law
    Nodal Analysis
    Kirchhoff's Current Law

    3. The attempt at a solution
    I used Nodal Analysis
    v1: ((v1)/1∠90°)+((v1)/2)+(((v1)-(v2))/4.55∠-90°)+(((v1)-(v2))/3) - (3∠62°)=0
    v2: 2+((v2)/(2.13∠-90°))+((v2)/5)+(((v2)-(v1))/4.55∠-90°)+(((v1)-(v2))/3)=0
    plugging that into the calculator and solving gives
    Which is NOT the book solution. Please tell me if I did this correctly.
  2. jcsd
  3. Mar 21, 2015 #2
    Your equations look correct, so just double check the values you obtained from the calculator.
  4. Mar 21, 2015 #3


    User Avatar

    Staff: Mentor

    I can confirm that the values look good, too.

    I suppose that the problem may have been modified a bit at some point and the answer key not updated.
  5. Mar 22, 2015 #4
    Excuse me this question is from which country?
  6. Mar 22, 2015 #5
    I am from the US. This question is from Engineering Circuit Analysis 8th Edition, by William H. Hayt Jr.
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