What is the formula for calculating the area of a circle?

The formula for calculating the area of a circle is given by Area = πr², where "r" represents the radius of the circle. This formula is derived from the relationship between the radius and the area as it simplifies the calculation of the space enclosed by the circular boundary.

In this formula, π (pi) is a constant approximately equal to 3.14, which represents the ratio of the circumference of the circle to its diameter. The square of the radius is necessary because the area pertains to two dimensions—length and width—hence it incorporates the radius squared.

This understanding of area is fundamental in HVAC applications, as calculating the area of ducts, pipes, or other circular components can be critical for airflow and system efficiency. Recognizing that this formula specifically pertains to circles helps distinguish it from other geometric shapes where different formulas would apply.