<question: The density of air is
A: How much air weighs per cubic foot
B: How much volume one pound of air occupies
C: The ratio of the weight of water to that of the same volume of water
D: The ratio of the amount of water vapor contained in a cu. ft. of air to the amount of moisture held at
saturation - ✔✔ correct answer A: How much air weighs per cubic foot
The specific volume of air is
A: How much air weighs per cubic foot
B: How much volume one pound of air occupies
C: The ratio of the weight of water to that of the same volume of water
D: The ratio of the amount of water vapor contained in a cu. ft. of air to the amount of moisture held at
saturation - ✔✔ correct answer B: How much volume one pound of air occupies
The relative humidity of air is
A: The percent of moisture air is holding as opposed to the amount it could hold if it were saturated
B: Always less than 100%
C: The most accurate measurement of how much water vapor is in a given body of air
,NATE Air Distribution
D: Used as a multiplier to size humidifiers - ✔✔ correct answer A: The percent of moisture air is holding
as opposed to the amount it could hold if it were saturated
As air is heated it
A: Contracts
B: Expands
C: Does not change its volume
D: Becomes more dense - ✔✔ correct answer B: Expands
The air pressure in a sealed balloon is
A: Static pressure
B: Velocity pressure
C: A combination of static and velocity pressures
D: None of the above - ✔✔ correct answer A: Static pressure
A blower connected to a length of duct
A: Creates static pressure which is then converted to velocity pressure
B: Creates velocity pressure directly
, NATE Air Distribution
C: Creates resistance to the flow of air
D: None of the above - ✔✔ correct answer A: Creates static pressure which is then converted to velocity
pressure
Velocity pressure is determined by
A: Subtracting static pressure from total pressure
B: Subtracting total pressure from static pressure
C: Dividing the total pressure by the static pressure
D: Subtracting the traverse pressure from the velocity - ✔✔ correct answer A: Subtracting static
pressure from total pressure
Velocity pressure can be mathematically converted to
A: CFM
B: FPM
C: Relative humidity
D: Inches of mercury vacuum - ✔✔ correct answer B: FPM
fpm = 4005 x (sqrt of Vp)