(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

A transmission line is made of aluminum wire 1 inch in diameter. What is the resistance of 20 miles of this wire?

2. Relevant equations

Resistance varies directly with the length of a wire and inversely with its cross-sectional area.

Resistivity of aluminum = 2.8 x 10-8

R=pl/A

Where l=32,186.88 meters

Find cross-sectional area.

R= 2.8 x 10-8 (31,186.88)/A =

3. The attempt at a solution

I'm stuck trying to find the cross-sectional area, A.

Also, the answer has to be in the same units as the problem, so does that mean I have to convert to inches and miles? The answer should be in ohms correct?

**Physics Forums | Science Articles, Homework Help, Discussion**

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

# Homework Help: Stuck-Resistivity problem

**Physics Forums | Science Articles, Homework Help, Discussion**