How many cmils is the cross-sectional area of a 4 AWG bare copper conductor?

The cross-sectional area of a conductor is measured in circular mils (cmils), which is a common unit for gauging the area of round wire. For a 4 AWG (American Wire Gauge) bare copper conductor, the area is defined based on standard tables that provide the diameter for different wire sizes.

A 4 AWG conductor has a diameter of approximately 0.2043 inches. To calculate the cross-sectional area in cmils, the formula used is:

Area (cmils) = (Diameter in inches)² x 1,000,000

Substituting the diameter for 4 AWG into the formula:

Area (cmils) = (0.2043)² x 1,000,000 ≈ 41740 cmils

This means that the cross-sectional area of a 4 AWG bare copper conductor is approximately 41,740 cmils, which corresponds to the correct answer, confirming that the calculation aligns with the established standard for wire sizes.