Find the resistivity constant homework

AI Thread Summary
The discussion revolves around calculating the conductance of a device with a current of 2 A and a potential difference of 60 V, leading to a resistance of 30 ohms. Participants clarify that conductance is defined as the inverse of resistance, G = 1/R. There is confusion regarding the need for the resistivity constant, with some mistakenly believing it is necessary for calculating conductance. Ultimately, it is confirmed that only the resistance is needed to find conductance, simplifying the problem. The interaction highlights the importance of carefully reading the homework question.
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Homework Statement


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?


Homework Equations


R= V/I
R= (resistivity)X (length)/Area


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..
 
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Why do you need the resistivity constant? Don't you just need to find the conductance, which is 1/R?
 


ideasrule said:
Why do you need the resistivity constant? Don't you just need to find the conductance, which is 1/R?
but don't i need the resistivity constant to find that to do find the conductance?
 


The conductance is defined in the question as 1/R, where R is resistance.
 


ideasrule said:
The conductance is defined in the question as 1/R, where R is resistance.

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

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