181. The mass of water vapour present in __________ is called absolute humidity.
1 m3 of wetair
1 m3 of dry air
1 kg of wet air
1 kg of dry air
✅ The correct answer is option B.
Heat Transfer, Refrigeration and Air Conditioning MCQs
182. The expression is used for calculating
relative humidity
humidity ratio
degree of saturation
pressure of water vapo
✅ The correct answer is option B.
183. In a domestic vapour compression refrigerator, the refrigerant commonly used is
CO2
Ammonia
R-12
all of these
✅ The correct answer is option C.
184. The refrigerant carbon dioxide is not widely used because of its __________ power require ments per tonne of refrigeration and high operating pressures.
low
high
✅ The correct answer is option B.
185. The wet bulb temperature at 100% relative humidity is __________ dew point temperature.
same as
lower than
higher than
✅ The correct answer is option A.
186. The heat is transferred by conduction, convection and radiation in
melting of ice
boiler furnaces
condensation of steam in condenser
none of these
✅ The correct answer is option B.
187. In case of liquids and gases, the heat transfer takes place according to
conduction
convection
radiation
none of these
✅ The correct answer is option B.
188. The index which corelates the combined effects of air temperature, relative humidity and air velocity on the human body, is known as
mean radiant temperature
effective temperature
dew point temperature
none of these
✅ The correct answer is option B.
189. The coefficient of performance of vapour compression refrigeration system is quite __________ as compared to air refrigeration system.
low
high
✅ The correct answer is option B.
190. The conditioned air supplied to the room must have the capacity to take up
room sensible heat load only
room latent heat load only
both room sensible heat and latent heat loads
none of the above
✅ The correct answer is option C.