What is the CFM delivered by a duct with an air velocity of 2,000 fpm and a cross-sectional area of 12” x 12”?

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To determine the CFM (Cubic Feet per Minute) delivered by the duct, you can use the formula:

CFM = Air Velocity (fpm) × Cross-Sectional Area (sq. ft.)

First, convert the dimensions of the duct from inches to feet. The cross-sectional area of the duct is 12 inches by 12 inches. To convert to feet, you divide by 12:

12 inches ÷ 12 = 1 foot

Thus, the cross-sectional area in square feet is:

Area = 1 ft × 1 ft = 1 sq. ft.

Next, you can insert the values into the formula using the air velocity of 2,000 fpm:

CFM = 2,000 fpm × 1 sq. ft. = 2,000 cfm

This calculation shows that when you have an air velocity of 2,000 feet per minute through a duct with a cross-sectional area of 1 square foot, the resulting airflow delivered is 2,000 cubic feet per minute. This confirms that the correct answer is indeed 2,000 cfm.