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Working out EMF of a cell

  1. May 21, 2008 #1
  2. jcsd
  3. May 21, 2008 #2

    Hootenanny

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  4. May 21, 2008 #3
    I know I need to find the difference of of the volts about the 2 resistors.

    it ends up being 1 volt, but how the hell does i(R+r)=emf come into that
     
  5. May 21, 2008 #4

    Hootenanny

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    That equation is valid only for two resistors in series, i.e. where a cell has an internal resistance r and is connected to a load resistance R.

    As I said previously, you need to apply Kirchoff's laws here.
     
  6. May 21, 2008 #5
    I did, the answer is 1

    just doesn't make sense.
     
  7. May 21, 2008 #6

    Hootenanny

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    I also have emf = 1V. So what doesn't make sense?
     
  8. May 21, 2008 #7
    Why do i have to count one of those volt readings as negative, and why inst it 1/r it looks like a a parallel
     
  9. May 21, 2008 #8

    Hootenanny

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    What is Kirchoff's voltage/loop law?
     
  10. May 21, 2008 #9
    no idea
     
  11. May 21, 2008 #10

    Hootenanny

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    How can you apply Kirchoff's voltage law if you don't know what it is?
     
  12. May 21, 2008 #11
    guessed, that the volts in the battery would have to make up for the difference. but why is the amps 0.06 out of 0.032, if the volts were 5.2 instead of 4.2 in the right part of the circuit it wouldn't fit the rule RI=v
     
    Last edited: May 21, 2008
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