Question

A wire of resistivity $\rho$ is stretched to double its length what will be its new resistivity?

Answer 1

• Resistivity is a property of the material which does not depend upon the length or cross-sectional area of the wire.
• Thus increasing the length will not affect the resistivity of the wire.
• Hence the new resistivity of the wire will be the same i.e $\rho$.

$\text{Note:}$ On changing dimensions, Resistivity does not change but Resistance of the wire changes, as $R=\frac{\rho l}{A}$