Resistors and Ohm's Law Video Lessons

Concept

# Problem: The diameter of a specific copper wire is 8.325 mm, and has a resistivity of 1.72 x 10-8Ω-m. Find the resistance of a 0.85 km length of such wire used for power transmission in Ω.

###### FREE Expert Solution

Resistance, R:

$\overline{){\mathbf{R}}{\mathbf{=}}\frac{\mathbf{\rho }\mathbf{l}}{\mathbf{A}}}$

A = πr2

r = D/2 = 8.325/2 = 4.1625 mm.

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###### Problem Details

The diameter of a specific copper wire is 8.325 mm, and has a resistivity of 1.72 x 10-8Ω-m.

Find the resistance of a 0.85 km length of such wire used for power transmission in Ω.