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Homework Help: Temperature Coefficient of Resistivity

  1. Apr 30, 2007 #1
    A coil of wire has a resistance of 37.800 Ω at 27.800 °C and 44.400 Ω at 56.000 °C. What is the temperature coefficient of resistivity? Do not enter units.

    Equation: R=R0[1+α(T-T0)]

    then i plugged in number to make the equation look like this:


    and i solve for X and i get X=.0402 and its wrong...

    anyone see something i dont?
  2. jcsd
  3. Apr 30, 2007 #2


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    Can you show more of your steps to your final answer? You're making a mistake somewhere.
  4. Apr 30, 2007 #3






    those are the steps i used...im not too sure about what to do with the 1+X part but that might be where im going wrong.
    Last edited: Apr 30, 2007
  5. Apr 30, 2007 #4


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    You can't add the 1 to the 28.2, since the units are not the same (it doesn't make sense to do that). You must go

    (44.4/37.8) - 1 = 28.2X

    in the next step to isolate X.
  6. Apr 30, 2007 #5
    ah! yeah now that you say it that doesnt make sense.. thank you very much!
  7. Apr 30, 2007 #6


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    You're welcome. :smile:
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