Question

The length of a wire is tripled and its area of crossection is doubled, how does it affect the resistivity of the wire. give reason in support of your answer.

Answer 1

we know, $R=\rho\frac{l}{A}$
where R is resistance of wire , $\rho$ is resistivity of wire material, l is length of wire and A is cross section area of wire.

but you should remember that resistivity is non chargeable quantity for a specific material if we change length and cross section area , it can change resistance of wire but resistivity remains constant.