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Homework Help: Circuit analysis in series vs. parallel

  1. Jun 6, 2010 #1
    I need to determine whether the resistors on this circuit are in series or in parallel. Here's my reasoning...

    They are not in series because the current going through each resistor is not equal: I1 [tex]\neq[/tex] I4 [tex]\neq[/tex] I5 *

    *This is assuming I've assigned current properly which I'm not sure I have. Please tell me if there's a mistake in how I've split the current and how to correct it.

    And they are not in parallel because the current flowing into each junction does not equal the current flowing out of each junction, because each junction splits into two currents.

    I think I can show this algebraically using Kirchhoff's rules, but I don't how to set up each electric potential because I don't know where each loop begins or ends, or if this circuit even constitutes a loop and Kirchhoff's rules apply.

    Please offer some guidance and help me understand how to analyze this properly. I really need to understand if these are in series or in parallel, and why.

    Attached Files:

    • IMG.jpg
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  2. jcsd
  3. Jun 6, 2010 #2
    In the second drawing, notice that some of the nodes with different designations are actually the same node. Redraw the circuit again but this time draw it so the ends of the resistors that are on the same node are close to each other.
  4. Jun 6, 2010 #3
    I don't know if 'nodes' are the same thing as 'junction points', but I think you're telling me to redraw the circuit like this... is this correct?

    Attached Files:

  5. Jun 7, 2010 #4
    Yes, nodes are the same as junction points and yes that is the way to redraw the circuit.
  6. Jun 7, 2010 #5
    awesome, thanks for the help... I didn't know you could combine junction points like that... I was trying to make sense of it by manipulating the equations for kirchhoff's rules...
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