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Homework Help: Easy Circuit Question

  1. Oct 9, 2006 #1
    Is the resistance of this circuit 10 ohms?

    http://img75.imageshack.us/img75/9229/littlecircuitro8.jpg [Broken]

    I can't prove anything to myself since the resistors aren't in parallel or series.

    I do notice that the potential at the top of the right side resistor is the same as at the bottom... So by Ohm's law the current through it should be zero, and so it's just sitting there not resisting anything. Hence, only the left resistor provides resistance to the circuit and R_total = 10 ohms.

    Am I correct? Because this just seems counter intuitive.

    Last edited by a moderator: May 2, 2017
  2. jcsd
  3. Oct 9, 2006 #2


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    You are correct. I donĀ“t see why do you say it is counter intuitive.
    The equivalent resistance of a resistor in parallel with a short-circuit is a short circuit.
    The equivalent resistance of a resistor in series with a short-circuit is the resistance of the resistor.
  4. Oct 9, 2006 #3
    I dunno... It just seems to me like perhaps a little bit of the current would get through. :smile:

    I guess if I looked at it as the current taking the path of least resistence, then yeah, I guess it's pretty intuitive. (Although, obviously, such an analogy couldn't extend to resistors in parallel)

    Anyways... Thanks!
  5. Oct 9, 2006 #4


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    Such analogy extends to resistors in parallel. The short-circuit has zero resistance, so all the current passes through it.
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