A wire $100\,cm$ long and $2.0\,mm$ diameter has a resistance of $0.7\, ohm$, the electrical resistivity of the material is ...........$ \times {10^{ - 6}}\,ohm \times m$
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$R = \frac{{\rho L}}{A} \Rightarrow 0.7 = \frac{{\rho \times 1}}{{\frac{{22}}{7}{{(1 \times {{10}^{ - 3}})}^2}}}$
$\rho = 2.2 \times {10^{ - 6}}\,ohm \times m$
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