Question

Which of the following would have the same resistance as a copper wire that
is 4 m long and has a cross-sectional area of 0.066 cm??
A. A copper wire that is 8 m long and cross-sectional area of 0.132
cm2
B. A copper wire that is 6 m long and cross-sectional area of 0.022
cm2
C. A copper wire that is 2 m long and cross-sectional area of 0.132
cm2
O D. A copper wire that is 1 m long and cross-sectional area of 0.0złhing
cm2

Answer 1

Answer:

Wire A

Explanation:

The resistance of a wire is given by:

$R=\frac{\rho L}{A}$

where

$\rho$ is the resistivity of the material

L is the length of the wire

A is the cross-sectional area

For wires made of same material, $\rho$ is the same, so we just need to compare the factor $L/A$ for the different wires and check which ones have the same ratio.

For the original wire:

$\frac{L}{A}=\frac{4}{0.066}=60.6$

For wire A:

$\frac{L}{A}=\frac{8}{0.132}=60.6$

For wire B:

$\frac{L}{A}=\frac{6}{0.022}=272.7$

For wire C:

$\frac{L}{A}=\frac{2}{0.132}=15.2$

For wire D:

$\frac{L}{A}=\frac{1}{0.022}=45.5$

Therefore, the wire that has the same resistance as the original wire is wire A.

Answer 2

Answer: your answer is A.

Explanation: just took the a p e x quiz :)