12-gauge copper wire has a radius of 1.03×10−3 m. (a) What is the resistance of 11.5 m of this wire at 20°C. (b) How much current will pass through the wire if a potential difference of 9.00 V is applied across it?(adsbygoogle = window.adsbygoogle || []).push({});

The resistivity for copper is 1.7E-8 ohm meters

For part a:

The equation is R=ρ(L/A) and A=∏r^{2}.

I solved for Area and got 3.33E-6 m^{2}.

Then I did R=1.7E-8(11.5/3.33E-6)

R=.0587 ohms.

However, when I plug this into the system it says it's wrong. What did I do incorrectly? I double-checked my multiplication and everything.

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# Homework Help: Resistivity of Copper Wire

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