The resistivity of iron is$1 \times {10^{ - 7}}\,ohm - m$. The resistance of a iron wire of particular length and thickness is $1\, ohm$. If the length and the diameter of wire both are doubled, then the resistivity in $ohm - m$ will be
A$1 \times {10^{ - 7}}$
B$2 \times {10^{ - 7}}$
C$4 \times {10^{ - 7}}$
D$8 \times {10^{ - 7}}$
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A$1 \times {10^{ - 7}}$
a (a) Resistivity of some material is its intrinsic property and is constant at particular temperature. Resistivity does not depend upon shape.
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