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Homework Help: Emf battery with resistor

  1. Jul 28, 2010 #1
    1. The problem statement, all variables and given/known data
    The question itself doesn't make sense to me, it says to find emf but the answer box has V=
    ?????????????????
    problem is an attachment.


    2. Relevant equations
    I=e/(r+R)
    Ir+IR=emf
    P=VI


    3. The attempt at a solution
    If it wants voltage thats simple P=I^2R P=V^2/R V=54.8V if it wants emf I need some pointers ...... Thanks for any help
     

    Attached Files:

    • PF.png
      PF.png
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      19.5 KB
      Views:
      101
  2. jcsd
  3. Jul 28, 2010 #2
    Dont worry - - solved V is emf
     
  4. Jul 29, 2010 #3
    Here emf is the voltage difference
     
  5. Jul 29, 2010 #4
    If a battery has no internal resistance, its EMF and its voltage are the same thing.
     
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