An 8-Gauge Copper Wire (Diameter = 3 $\times$ 10⁷ A/m²
B)3 $\times$

Multiple Choice

An 8-gauge copper wire (diameter = 3.665 mm) carries a current of 40 A.The current density of the wire is

A) 1.52 $\times$ 10⁷ A/m²
B) 3.79 $\times$ 10⁶ A/m²
C) 1.90 $\times$ 10⁶ A/m²
D) 1.21 $\times$ 10⁶ A/m²
E) None of these is correct.