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## Homework Statement

A rectangle bar of iron is [tex]2cm[/tex] by [tex]2cm[/tex] in cross section. Calculate its resistance if the resistivity of iron is [tex]11 \times 10^{-8}\Omega{m}[/tex].

## Homework Equations

[tex]R = \frac{Pl}{A}[/tex]

## The Attempt at a Solution

[tex]R = \frac{Pl}{A}[/tex]

[tex]A = 2 \times 2 \times 10^-4 = 4 \times 10^{-4}m[/tex]

[tex]P = 11 \times 10^{-8}\Omega{m}[/tex]

How is it possible to find the resistance If I don't have the length?