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Homework Help: Find the resistivity constant homework

  1. Feb 27, 2010 #1
    1. The problem statement, all variables and given/known data
    The conductance G of a device is defined to be the inverse of its resistance, G=1/R. What is the conductance of a device through which the current is 2 A when a potential difference of 60 V is applied?


    2. Relevant equations
    R= V/I
    R= (resistivity)X (length)/Area


    3. The attempt at a solution
    I first found the resistance by using the first equation, and got 30 ohms but then I get stuck...because I don't see any other formulas that that uses resistance that allows me to find the resistivity constant...and I don't have the length and area for the second equation..
     
  2. jcsd
  3. Feb 27, 2010 #2

    ideasrule

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    Re: Resistance

    Why do you need the resistivity constant? Don't you just need to find the conductance, which is 1/R?
     
  4. Feb 27, 2010 #3
    Re: Resistance

    but don't i need the resistivity constant to find that to do find the conductance?
     
  5. Feb 27, 2010 #4

    ideasrule

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    Re: Resistance

    The conductance is defined in the question as 1/R, where R is resistance.
     
  6. Feb 27, 2010 #5
    Re: Resistance

    Ohh!! I'm so stupid I didn't even read the question properly...:grumpy:
    Thanks for clearing things up
     
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