Regarding the Branch Current Method

Discussion in 'Homework Help' started by nshepar2, Dec 18, 2011.

  1. nshepar2

    Thread Starter New Member

    Oct 13, 2011
    So I am working on the different methods of circuit analysis and can do KVL and KCL fine. But when I work the problem out that is at this link

    I get an answer that goes in the opposite direction. I get 5A and -1A respectively, and I have my reason for why the 1A is negative, since the 28V DC source is over powering the 7V source and pushing the current backwards through the 1 ohm resistor and 7V source. But what I don't get is why the 5A is flowing counter clockwise in the answer on the page?

    My KVL equations are based on the positive terminals of the sources being up and the current flowing clockwise in the left loop and counterclockwise in the right loop.

    Left: 28V = 6Ω(I1) + 2Ω(I2)
    Right: 7V = 2Ω(I1) + 3Ω(I2)

    I get for the left 5A flowing clockwise and for the right -1A flowing CCW. I also know conventional from electron flow, but since I set the current flow direction why is the answer reversed? Is this tutorial using electron current flow?

    Same thing happens for me when I do the mesh analysis, right answer, but opposite answer from the website.

  2. t_n_k

    AAC Fanatic!

    Mar 6, 2009
    The AAC learning material is based on electron flow - if you get the same magnitudes but opposite directions using the conventional current analysis taught just about everywhere else your working is probably correct.