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Which way is the current flowing?

  1. Feb 25, 2007 #1
    Please click on the image to make it bigger

    http://img184.imageshack.us/img184/2218/thisoneuf5.th.jpg [Broken]

    I'm having real difficulty picturing how the current is flowing in this circuit with the given solution.

    From the 5v source into node [tex] v_2[/tex] is the current flowing from left to
    right into this node?

    These are the nodal equations that I would use to solve this problem, however they are wrong. Why?

    At node two I would have the current flowing from left to right from the source into this node. I would have the 6mA flowing into this node. Finally I would have a current flowing out of this node from left to right. So I have 2 currents entering this node and one leaving

    [tex] \frac{V_2-5}{200} + 6mA = \frac{V_0-V_2}{6000}[/tex]

    at node two

    [tex]\frac{V_0-V_2}{6000} = \frac{V_0-(-6)}{3000}[/tex]
    Last edited by a moderator: May 2, 2017
  2. jcsd
  3. Feb 25, 2007 #2
    I agree with your equations

    is it just your final result that is wrong? because if so, it's probably that (v2-5)/200 instead of (v2-5)/2000

    oh and you converted kOhm to Ohm but didn't convert mA to A
    Last edited: Feb 25, 2007
  4. Feb 25, 2007 #3
    if you are considering your equations to be wrong based on the solution that is provided...i believe there is an error in the solution provided

    for the node in between r2 and r3, the solution provided said that the current coming into that node was (vo-v2)/r2 but for the previous node, that same current was expressed as (v2-vo)/r2
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