Air Movement and Measurement

Question 1

The conditions in the atmosphere refer to ______?

Answer 1

Weather

Question 2

Long-term weather trends for a given region refers to ______?

Answer 2

Climate

Question 3

How warm the combination of humidity and temperature feels to an occupant of a space is ______ temperature.

Answer 3

Equivlaent

Question 4

The atmosphere is approximately 23% ______ by weight.

Answer 4

Oxygen

Question 5

______ makes up 0.03% to 0.04% of the atmosphere and is absorbed by growing plants.

Answer 5

Carbon Dioxide

Question 6

The majority of the atmosphere is composed of ______.

Answer 6

Oxygen

Question 7

A gas that is very light and present in most fuels is ______.

Answer 7

Hydrogen

Question 8

According to Bernoulli’s principle, ______ the velocity of air decreases the pressure

Answer 8

Increasing

Question 9

Air has weight, volume, and ______?

Answer 9

Temperature
Heat Conductivity
Specific Heat

Question 10

One pound of air at standard conditions (14.7 psia @ 69.8 degrees F) occupies ______ ft squared.

Answer 10

13.341 ft squared

Question 11

By dividing the weight of air by the volume it occupies, you can calculate the ______ of the air.

Answer 11

Density

Question 12

The amount of moisture in an air sample compared to the total amount of moisture the same sample would hold if it were completely saturated at the same temperature defines the term ______.

Answer 12

Relative Humidity

Question 13

(T/F) Since dry air prevents rapid evaporation of moisture from a surface, the surface does not cool as quickly as it would with moist air.

Answer 13

False

Question 14

(T/F) The amount of moisture that a set volume of air can hold depends on its air temperature.

Answer 14

True

Question 15

(T/F) Wet-bulb temperature will be higher than dry-bulb temperature at 100% humidity.

Answer 15

False.

They will be the same

Question 16

Define dew point.

Answer 16

Dew point is the temperature below which water vapor in the air will start to condensate.

Question 17

The combined effect of dry-bulb temperature, wet-bulb temperature, and air movement that provides an equal sensation of warmth and cold describes the term ______.

Answer 17

Effective temperature

Question 18

(T/F) An increase in wind velocity increases heat loss of a heated structure, thereby impacting the efficiency of a heating system.

Answer 18

True

Question 19

The volume of air flowing through a duct is calculated in ______.

Answer 19

feet per minute

Question 20

(T/F) Velocity pressure is exerted when the airflow is slowed or stopped.

Answer 20

True

Question 21

Make-up air is necessary for fuel-burning appliances because oxygen is necessary for ______.

Answer 21

Combustion

Question 22

Define “Enthalpy.”

Answer 22

The total amount of heat in a substance, calculated from an accepted reference temperature. Specific Enthalpy is enthalpy per unit of mass.

Question 23

What is heat that brings about a change in state with no change in temperature?

Answer 23

Latent heat

Question 24

Heat that causes a change in the temperature of a substance is ______.

Answer 24

Sensible heat