CPA Application Equipment and Calibration 3

Question 1

What is the purpose of a pressure regulator in a pesticide spray system?

Accepted Answer

To maintain consistent operating pressure regardless of pump fluctuations

Answer

A pressure regulator maintains a steady, pre-set operating pressure by releasing excess pressure back to the tank or bypass line.

Question 2

In the formula GPA = (GPM × 5940) / (MPH × W), what does the value 5940 represent?

Accepted Answer

A conversion constant that accounts for minutes and distance units

Answer

The constant 5940 is derived from converting miles per hour and nozzle spacing into a per-acre basis (5280 ft/mile × 60 min/hr / 12 inches per foot × nozzle spacing denominator).

Question 3

Which nozzle type produces the largest droplet size and is therefore most suitable for minimizing drift in windy conditions?

Accepted Answer

Air induction (venturi) nozzle

Answer

Air induction nozzles mix air into the spray stream, producing large air-filled droplets that are much less prone to drift than conventional nozzles.

Question 4

A granule applicator is set to release 50 lbs of granules per acre. The label requires 60 lbs per acre. To increase output without changing ground speed, the applicator should:

Accepted Answer

Use a larger orifice or wider opening on the metering gate

Answer

Opening the metering gate wider increases the volume of granules released per unit of time, raising the application rate.

Question 5

When calibrating a rotary spreader, the applicator catches material in collection pans placed under the distribution pattern. What is the primary purpose of this step?

Accepted Answer

To determine the effective swath width and distribution uniformity

Answer

Catching granules in collection pans across the spread pattern reveals the effective swath width and whether distribution is uniform from center to edge.

(CPA) Certified Pesticide Applicator Practice Test

(CPA) Certified Pesticide Applicator Practice Test

CPA Application Equipment and Calibration 3