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  1. Apr 19, 2015 #1
    Could you solve this?
  2. jcsd
  3. Apr 19, 2015 #2

    Doc Al

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    Staff: Mentor

    That's a famous physics "puzzle". Can you solve it?
  4. Apr 19, 2015 #3
    I believe back in college I had to calculate the continuous case of this, e.g. you stick two metal rods into the ground a meter apart. What is the resistance between the rods given the resistivity of the ground.
    (EDIT: Or maybe I just imagine having solved it. I definitely pondered it in the past)

    The key insight in this problem is that you calculate the total resistance of it by calculating resistance along paths that are all electrically parallel with each other. More importantly, to be able to do so, you choose the paths so that there is no current flowing between those paths. That scenario happens when two neighboring paths have the same potential along their paths.

    Sorry, that's all I recall :)
  5. Apr 19, 2015 #4
    NO, I cannot solve it :(
  6. Apr 19, 2015 #5
    Just FYI, there's a neat web page on the matter that calculates it.
  7. Apr 19, 2015 #6
  8. Apr 19, 2015 #7
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