Coursework - Determining Resistivity

AI Thread Summary
The discussion focuses on calculating resistivity (ρ) in an experiment involving nichrome wire. The user has derived the formula ρ/AxV = 6.4 but is confused about the units, specifically needing to convert area (A) from mm to m. They report obtaining a very small resistivity value of 0.0016096, which raises concerns about the accuracy of their calculations. Clarification is sought on the meaning of variables A, x, and V, as well as the significance of the wire gauge (28 swg). The conversation emphasizes the importance of clear communication and using provided templates for homework questions.
coolnufc
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Hi guys, I am trying to work out ρ in an experiment.

Ive got down to ρ/AxV = 6.4
I know V = 2 and A=0.0907mm, but it should be m.

If i then work it out i get a stupidly small answer. Anyone help me out. Its like 0.0016096
 
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It was nichrome wire (28 swg) i was using if that helps
 
So, what's the problem?
What is A, x and V? Why should it be m?
What does 28swg mean?
 
coolnufc said:
Hi guys, I am trying to work out ρ in an experiment.

Ive got down to ρ/AxV = 6.4
I know V = 2 and A=0.0907mm, but it should be m.

If i then work it out i get a stupidly small answer. Anyone help me out. Its like 0.0016096

I agree with Engineer -- you need to be much clearer in your question. It would have helped if you had used the Homework Help Template that you are provided when you start a new homework thread. Please try to re-phrase your question in the form of the template:

 
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