A 75-m length of copper wire whose resistivity is 1.7 $\times$
10^-8 $\Omega$ . m has a resistance of 1.6 $\Omega$ . The diameter of the wire is

Question

A 75-m length of copper wire whose resistivity is 1.7 $\times$ 10^-8 $\Omega$ . m has a resistance of 1.6 $\Omega$. The diameter of the wire is

Quizplus · Accepted Answer

To find the diameter, use the formula for resistance: $ R = \rho \frac{L}{A} $. Rearrange to find the cross-sectional area $ A = \frac{\rho L}{R} $. Then, use $ A = \pi (\frac{d}{2})^2 $ to solve for the diameter $ d $. Plugging in the values, $ A = \frac{1.7 \times 10^{-8} \times 75}{1.6} $, and solving for $ d $, we find $ d \approx 1.0 $ mm.

A 75-M Length of Copper Wire Whose Resistivity Is 1 ×\times×

A 75-M Length of Copper Wire Whose Resistivity Is 1 $\times$