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AP® Physics 1 & 2

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Moderate

Resistance: Wire Cross-Sectional Area

APPH12-X934TG

One piece of metal wire has a resistance $R$. A second piece of wire is completely identical to the first, except that it has half as large of a cross-sectional diameter.

In terms of $R$, what is the resistance of this second piece of wire?

A

$\cfrac{R}{4}$

B

$\cfrac{R}{2}$

C

$2R$

D

$4R$