Answer:
Resistivity = (1.726 × 10⁻⁸) Ωm
Comparing this answer with the resistivity of the listed materials in the question, this resistivity matches that of Copper the most.
Hence, the material is Copper.
Option A is correct. Copper.
Explanation:
Given,
I = 30.0 A
d = 0.326 cm = 0.00326 m
E = 0.062 V/m
The current density for the wire is given as
J = (I/A)
where J = current density = ?
I = current = 30.0 A
A = Cross sectional Area of the wire = (πd²/4) = [π×(0.00326²)/4] = 0.0000083503 m²
J = (30 ÷ 0.0000083503) = 3,592,685.3 A/m²
On a microscopic scale, Ohm's law can be stated as
E = Jρ
where E = Electric field = 0.062 V
J = Current density = 3,592,685.3 A/m²
ρ = Resistivity of the material = ?
ρ = (E/J)
ρ = 0.062 ÷ 3,592,685.3 = (1.726 × 10⁻⁸) Ωm
Comparing this answer with the resistivity of the listed materials in the question, this resistivity matches that of Copper the most.
Hence, the material is Copper.
Hope this Helps!!!
