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Homework Help: How is internal resistance of a cell related to temperature

  1. Feb 10, 2008 #1
    Relevant equations

    int rest =emf - terminal potential / current

    The attempt at a solution

    Since Emf of a cell is inversely proportional to temp (From Nernst Equation of Emf of a cell), from the above equation, if temp is high, E is low, therefore r is low. So, acc. to me,
    r decreases with increase in temp. But obviously, if E is decreasing, this must mean that r has increased. I am confused. Please help.

    Edit: If we think in terms of solutions, then dissociation increases on heating, which means more ions available in cell, which means increase in conductance, which leads to the conclusion that resistance of the cell decreases with increase in temp.

    Mr V
    Last edited: Feb 10, 2008
  2. jcsd
  3. Feb 11, 2008 #2
    I found out on the net that internal resistance decreases with increase in temperature.
  4. Feb 11, 2008 #3
    it's r = (E-V)/I

    and I and V do not remain constant if you change the temperature. I don;t think you can
    use this formula to see what happens to R unless you measure I and V.
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