Question

A 5.5 m long aluminum wire has a resistance of 0.40 Ω, ρ = 2.82x10-8 Ωm and α= 4.29x10-3 oC-1. Its conductivity is:Group of answer choices3.6x107 (1/Ωm)2.5x103 (1/Ωm)230 (1/Ωm)

Answer 1

The correct answer is 3.6×10⁷ (1/Ωm)

Given,

The length of the aluminum wire, l=5.5 m

The resistance of the wire, R=0.40 Ω

The resistivity of the wire, ρ=2.82×10⁻⁸ Ωm

The resistivity is given by the inverse of the conductivity of a material.

Thus the conductivity of the given wire is,

`c=(1)/(\rho)`

On substituting the known values,

`\begin{gathered} c=(1)/(2.82*10^(-8)) \\ =3.6*10^7\text{ (1/}\Omega\text{m)} \end{gathered}`

Therefore the conductivity of the given aluminum wire is (1/Ωm)