Applied Thermodynamics (3161910) MCQs

MCQs of Psychrometry

Showing 21 to 30 out of 60 Questions
21.
The ratio of the actual specific humidity to the specific humidity when the air is saturated at the same dry bulb temperature is called
(a) humidity ratio
(b) relative humidity
(c) absolute humidity
(d) degree of saturation
Answer:

Option (d)

22.
For unsaturated air, the dew point temperature is __________ wet bulb temperature.
(a) equal to
(b) less than
(c) more than
(d) can’t predict
Answer:

Option (b)

23.
Which of the following statement is TRUE?
(a) During cooling and humidification process, the enthalpy of air decreases
(b) During cooling and humidification process, the enthalpy of air increases
(c) During cooling and humidification process, the enthalpy of air remains constant
(d) During cooling and humidification process, the enthalpy of air may increase, decrease or remain constant depending upon the temperature of the wet surface
Answer:

Option (d)

24.
During humidification process __________ remains constant.
(a) relative humidity
(b) dry bulb temperature
(c) dew point temperature
(d) wet bulb temperature
Answer:

Option (b)

25.
Dry bulb temperature is the temperature of air recorded by a thermometer, when
(a) it is not affected by the moisture present in the air
(b) its bulb is surrounded by a wet cloth exposed to the air
(c) the moisture present in it begins to condense
(d) none of the above
Answer:

Option (a)

26.
In an air washer system, if the temperature of the spraying water is higher than the dry bulb temperature of entering air, then the air is
(a) heated and dehumidified
(b) heated and humidified
(c) cooled and humidified
(d) cooled and dehumidified
Answer:

Option (b)

27.
The atmospheric air at dry bulb temperature of 15°C enters a heating coil maintained at 40°C. The air leaves the heating coil at 25°C. The by-pass factor of the heating coil is
(a) 0.376
(b) 0.4
(c) 0.6
(d) 0.67
Answer:

Option (c)

28.
The mass of water vapour present in __________ is called absolute humidity.
(a) 1 cubic meter of wet air
(b) 1 cubic meter of dry air
(c) 1 kg of wet air
(d) 1 kg of dry air
Answer:

Option (b)

29.
The wet bulb depression indicates __________ humidity of the air.
(a) absolute
(b) relative
(c) specific
(d) any of the above
Answer:

Option (b)

30.
The evaporative cooling systems are
(a) environment friendly
(b) offer lower initial and lower running cost
(c) easier to maintain and fabricate
(d) all of the above
Answer:

Option (d)

Showing 21 to 30 out of 60 Questions