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Homework Help: Circuit - Current

  1. Mar 15, 2007 #1
    1. The problem statement, all variables and given/known data
    http://img65.imageshack.us/img65/4307/mymymyyw3.th.png [Broken]
    Find the current on the 20 ohm resistor.
    2. Relevant equations
    3. The attempt at a solution
    Well, I'm fairly positive that the two 10 ohm resistors will transport the same amount of current so:

    25V - I*25 - I2*10 = 0
    25V + I3*5 - 10*I2 = 0
    I = 2*I2 + I3

    When I solve using those equations, I get I2 = 1.36 A and I = .45 A (I is double of what it should be).
    Could anyone look at my equations and tell me what's wrong?
    Last edited by a moderator: May 2, 2017
  2. jcsd
  3. Mar 15, 2007 #2


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    Homework Helper

    Reduce the circuit as much as possible. You put the 5 ohm and 20 ohm in series already. There is also the 5 ohm and 10 ohm that are in parallel. If you reduce that you will then have a circuit with two loops. Then you will only have two unknowns to deal with.
  4. Mar 15, 2007 #3
    Ok, now i've got it, thanks
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