1. Limited time only! Sign up for a free 30min personal tutor trial with Chegg Tutors
    Dismiss Notice
Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Super-node question, one equation or two?

  1. Sep 8, 2014 #1
    1. The problem statement, all variables and given/known data
    Use the mesh current method to solve for the power dissipated

    2. Relevant equations
    v1+v2+..vn=0
    i=v/R
    p=i*v


    3. The attempt at a solution
    I was trying to solve the question using two equations,
    eq1) 20=4*i1+i1
    eq2) -90=9*i2+6*i2
    eq3)i2-i1=6A...

    So I obviously made a mistake since the 6A is doing nothing in my equations, and both equations 1 and 2 have no unknowns. Am I suppose to just use one equation, and use the super node as my second? How can I tell when I need to use only one equation?
     

    Attached Files:

  2. jcsd
  3. Sep 8, 2014 #2

    donpacino

    User Avatar
    Gold Member

    In both eq1 and eq2 you are missing the voltage drop Vo
     
  4. Sep 8, 2014 #3

    gneill

    User Avatar

    Staff: Mentor

    You are asked to use mesh equations, so rather than a supernode, you want a supermesh. You should write one equation for the supermesh and one constraint equation tying the two "normal" mesh currents to the 6 A source.
     
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook

Have something to add?
Draft saved Draft deleted



Similar Discussions: Super-node question, one equation or two?
Loading...