A square meter (symbol: m²) is a unit of area in the International System of Units (SI), which is the metric system commonly used in many countries worldwide. It is defined as the area of a square with sides that each measure one meter in length.
To give you a visual sense of the size of a square meter, imagine a square that is one meter long on each side. It is equal to 10,000 square centimeters (cm²) or 0.0001 hectares (ha). In square feet, one square meter is approximately 10.7639 square feet (sq ft).
The square meter is the primary unit for measuring area in the metric system and is widely used in various scientific, engineering, and everyday applications for describing land area, room dimensions, and many other surface measurements.
A circular mil (often abbreviated as cmil or kcmil) is a unit of area used primarily in the United States for measuring the cross-sectional area of a round wire or cable. It is a convenient unit for specifying the size of electrical conductors.
One circular mil is equal to the area of a circle with a diameter of one mil (1/1000th of an inch) or approximately 0.000000506707 square inches (in²). In metric units, one circular mil is approximately equal to 0.000001273 square millimeters (mm²).
Circular mils are commonly used in the American Wire Gauge (AWG) system to specify wire sizes. The AWG system assigns a unique number to each wire size, and this number is related to the wire's cross-sectional area in circular mils. For example, a larger AWG number corresponds to a smaller wire size with fewer circular mils, while a smaller AWG number corresponds to a larger wire size with more circular mils. This system allows for easy reference and selection of wire sizes for various electrical applications.