With the sprayer stationary, you collect 1 pint (16 oz) of solution in 15 seconds from one nozzle. There are 4 nozzles with a combined swath width of 8 feet. How many gallons per acre will you be applying when traveling at 10 mph?

• A. 8
• B. 12
• C. 16
• D. 20

Answer: (B)

GPA is found from how much liquid you put on per minute and how much area that liquid covers per minute as you move. Each nozzle delivers 1 pint in 15 seconds, which is 0.125 gallon in 15 seconds, or 0.00833 gallon per second. That equals 0.5 gallon per minute per nozzle. With four nozzles, the total flow is 2.0 gallons per minute.

Travelling 10 mph translates to 880 feet per minute. With a swath width of 8 feet, you cover 880 × 8 = 7,040 square feet each minute. Since 1 acre = 43,560 square feet, you cover 7,040 / 43,560 ≈ 0.1614 acres each minute.

Gallons per acre = total flow rate ÷ acres per minute = 2.0 ÷ 0.1614 ≈ 12.4 gallons per acre. Rounding gives about 12 gallons per acre, which matches the expected choice.