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Homework Help: Temperature increase due to increase of resistance

  1. May 14, 2012 #1
    1. The problem statement, all variables and given/known data
    To what value would you have to raise the temperature of a copper wire (originally at 20 deg/C ) to increase its resistance by 14 % ?


    3. The attempt at a solution
    temp. coeffic of copper = 0.004
    delta T = 0.14/0.004

    delta T = 35 deg/C

    why is this incorrect.
     
  2. jcsd
  3. May 14, 2012 #2
    You need to realise that the temp coefficient (0.004/C) means that the resistance of copper Changes by 0.004 x resistance at 0C for each degree change in temperature
    So R = Ro(1 + αt) where R = resistance at tC and α = temp coeff of resistance
    Have you met this equation?
    correction made
     
    Last edited: May 14, 2012
  4. May 14, 2012 #3
    Yeh I have seen the equation somewhere in the textbook thanks for help
     
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