Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Homework Help: Help with supernode question

  1. Oct 15, 2008 #1
    need help to solve this problem using node analysis

    find the power deliverd by the dependent voltage source

    http://i170.photobucket.com/albums/u270/weiqiangt/Photo213.jpg


    need to use node voltage analysis


    i tried using this equation: (v1-160)/10 + (v1/100) + (v1-150 Io)/ 20

    but it looks like the ans is wrong
     
  2. jcsd
  3. Oct 15, 2008 #2

    CEL

    User Avatar

    There are two resistors in the branch containing the dependent source: 20 ohm and 30 ohm.
    The current Io is a function of V1 and the 100 ohm resistor.
    Finally, you must write a zero in the second term of your equation.
     
  4. Oct 15, 2008 #3
    you mean my equation will look like this:

    (v1-160)/10 + (v1/100) + (v1-150 Io)/ 20 = 0

    Io - v1/100

    then what about my constraint equation? i really dunno how to do it
     
  5. Oct 15, 2008 #4

    CEL

    User Avatar

    Nope!
    You should have
    (v1-160)/10 + (v1/100) + (v1-150 Io)/ 50 = 0
    Io = -v1/100

    What constraint equation?
     
  6. Oct 16, 2008 #5
    i use this equation (v1-160)/10 + v1/100 + (v1-150 io)/50 = 0

    then

    io = -v1/100

    my v1 = 100V and io = -1A

    need to find the power in the dependant source... but it seems with this equation i cannot get the ans....

    the actual ans is 750W from electric circuit 8th edition by nillsson riedel
     
  7. Oct 16, 2008 #6

    CEL

    User Avatar

    What is the voltage of the dependent source?
    What is the current delivered by that source?
    p = VI.
     
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook