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Can someone help me find the equivalent resistance

  1. Mar 11, 2005 #1
    For this question im pretty sure Im doing everything right but I just cant get the right answer. Diagram below. This is the question. Find the equivalent resistance of the circuit shown in the diagram, where R1 = 3 Ω, R2 = 2 Ω, R3 = 4 Ω, R4 = 1 Ω, R5 = 1 Ω, R6 = 2 Ω, and R7 = 2 Ω.

    What I did was R4 and R3 in parallel, R6 and R5 in series, R1 and R2 in series, R12 and R7 in parallel, then R65 and R43 in series together, and finally R6543 in series with R127. I keep getting 2.07 ohms as my answer. If you can make out what I said can anyone help me?

    Attached Files:

  2. jcsd
  3. Mar 11, 2005 #2
    One problem I see with your calculations is you took R1 and R2 in series, but R2 is in series with R3//R4

    R1 will be one of the last ones you can reduce
  4. Mar 11, 2005 #3
    OK I still cant get it

    I have R3/R4 in parallel. Then I took that in series with R2. Then I took that in series with R6//R5. Then all of that in series with R7. And finally that in parallel with R1. Does all that sound right?
  5. Mar 11, 2005 #4


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    Are you sure about that?

    Are you sure about that?

    Tip: Once you replace two resistors with an equivalent resistance, draw the circuit again with that replacement. That way, you will be able to see the relationships amongst the remaining resistors, instead of visualising it all in your head.
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