Power Engineering - 4B10 Practice
Exam Questions & Answers (Grade
A+)
Which of the following statements about duct leakage losses is
true?
a. The effects of air leakage in supply air ducts are the same as
those in return ducts.
b. For insulated supply air ducts located within the conditioned
spaces, determination of air leakage is evaluated based on
judgment, depending on whether leaked air enters the conditioned
space, or is lost.
c. Losses from bare supply air ducts within the conditioned space
have a substantial impact on loss calculations.
d. Air leakage varies from 40% to 45%. -
correct answer ✅b. For insulated supply air ducts located within
the conditioned spaces, determination of air leakage is evaluated
based on judgment, depending on whether leaked air enters the
conditioned space, or is lost.
The propeller axial flow fan:
a. Produces low capacity, low pressure air movement
,Power Engineering - 4B10 Practice
Exam Questions & Answers (Grade
A+)
b. Finds application in unit heaters, air-cooled condensers, and as
an exhaust fan for ventilation purposes
c. Is widely used in commercial air conditioning ducting
d. Requires the least power at minimum air delivery -
correct answer ✅b. Finds application in unit heaters, air-cooled
condensers, and as an exhaust fan for ventilation purposes
Wet-bulb temperature is:
a. The temperature indicated by a thermometer whose bulb
covered by a water-wetted wick, and exposed to a rapidly moving
stream of air
b. The dew point temperature
c. Always less than the dry-bulb temperature
d. The product of the dry-bulb temperature times the relative
humidity. -
correct answer ✅a. The temperature indicated by a thermometer
whose bulb covered by a water-wetted wick, and exposed to a
rapidly moving stream of air
, Power Engineering - 4B10 Practice
Exam Questions & Answers (Grade
A+)
Air duct velocity pressure is measured by connecting a:
a. Manometer to the side of an air duct
b. Bourdon tube to the air duct
c. Pressure gauge to the side of a duct, with a sensing tube
extending inside of the duct directed toward the airflow
d. Manometer to the side of a duct, with a sensing tube extending
inside of the duct directed toward the airflow -
correct answer ✅d. Manometer to the side of a duct, with a
sensing tube extending inside of the duct directed toward the
airflow
Air washers can achieve dehumidification when
a. the water temperature is greater than the dry bulb temperature.
b. the spray water is cooled to below the dew point.
c. the return air is more humid than the outside air.
d. the specific humidity of the air is greater than the relative
humidity. -
Exam Questions & Answers (Grade
A+)
Which of the following statements about duct leakage losses is
true?
a. The effects of air leakage in supply air ducts are the same as
those in return ducts.
b. For insulated supply air ducts located within the conditioned
spaces, determination of air leakage is evaluated based on
judgment, depending on whether leaked air enters the conditioned
space, or is lost.
c. Losses from bare supply air ducts within the conditioned space
have a substantial impact on loss calculations.
d. Air leakage varies from 40% to 45%. -
correct answer ✅b. For insulated supply air ducts located within
the conditioned spaces, determination of air leakage is evaluated
based on judgment, depending on whether leaked air enters the
conditioned space, or is lost.
The propeller axial flow fan:
a. Produces low capacity, low pressure air movement
,Power Engineering - 4B10 Practice
Exam Questions & Answers (Grade
A+)
b. Finds application in unit heaters, air-cooled condensers, and as
an exhaust fan for ventilation purposes
c. Is widely used in commercial air conditioning ducting
d. Requires the least power at minimum air delivery -
correct answer ✅b. Finds application in unit heaters, air-cooled
condensers, and as an exhaust fan for ventilation purposes
Wet-bulb temperature is:
a. The temperature indicated by a thermometer whose bulb
covered by a water-wetted wick, and exposed to a rapidly moving
stream of air
b. The dew point temperature
c. Always less than the dry-bulb temperature
d. The product of the dry-bulb temperature times the relative
humidity. -
correct answer ✅a. The temperature indicated by a thermometer
whose bulb covered by a water-wetted wick, and exposed to a
rapidly moving stream of air
, Power Engineering - 4B10 Practice
Exam Questions & Answers (Grade
A+)
Air duct velocity pressure is measured by connecting a:
a. Manometer to the side of an air duct
b. Bourdon tube to the air duct
c. Pressure gauge to the side of a duct, with a sensing tube
extending inside of the duct directed toward the airflow
d. Manometer to the side of a duct, with a sensing tube extending
inside of the duct directed toward the airflow -
correct answer ✅d. Manometer to the side of a duct, with a
sensing tube extending inside of the duct directed toward the
airflow
Air washers can achieve dehumidification when
a. the water temperature is greater than the dry bulb temperature.
b. the spray water is cooled to below the dew point.
c. the return air is more humid than the outside air.
d. the specific humidity of the air is greater than the relative
humidity. -