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Homework Help: Nodal analysis help

  1. Jun 17, 2008 #1
    1. The problem statement, all variables and given/known data

    Consider the circuit shown (attached). Calculate the voltage v and calculate the power for the 2A current source. In this particular case, is it supplying or absorbing power?

    2. Relevant equations

    3. The attempt at a solution

    I know that there is 2A flowing around the circuit so no point in using loop equations. I dont think nodal analysis would be of much help or would it?

    Attached Files:

  2. jcsd
  3. Jun 17, 2008 #2


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    Homework Helper

    You're right, there's no need for loop equations. In this case just mark out all the nodes, and taking into account the direction of the current in the circuit, calculate the voltage at all the nodes using an arbitrary starting point of 0V in the circuit, remembering to minus potential when you cross over from + to - of a circuit element and add potential when you do the opposite. You should be able to get the potential at the point just above the 2A current source.

    From there you can calculate the power absorbed/supplied by the source.
  4. Jul 19, 2010 #3
    I would use KVL and the conservation of energy in a loop for a beginning.Since we know the value of each independent source, followed by convention sign we should be able to figure out how much energy left across the resistor. If the left energy is negative , then it is supplying the power. If it is a positive, then is is observing the power.
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