Top 250+ Solved Refrigeration and Air conditioning MCQ Questions Answer
Q. Electrolux refrigerators is
a. Vapour compression refrigerator with one compressor
b. vapour absorption refrigerator with no pump
c. vapour absorption refrigerator with one aqua pump
d. None of the above
Q. .In a psychrometric chart, the vertical lines parallel to the ordinate indicate
a. Dry bulb Temperature
b. Wet bulb Temperature
c. Specific humidity
d. Enthalpy of saturation
Q. Which of the following statements are TRUE?
a. Thermodynamic WBT is a property of moist air, while WBT as measured by wet bulb thermometer is not a property
b. Both the thermodynamic WBT and WBT as measured by wet bulb thermometer are properties of moist air
c. Under no circumstances, dry bulb and wet bulb temperatures are equal
d. Wet bulb temperature is always lower than dry bulb temperature, but higher than dew point temperature
Q. Which of the following statements are 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
Q. An air stream at a flow rate of 1 kg/s and a DBT of 30 C mixes adiabatically with another air stream flowing with a mass flow rate of 2 kg/s and at a DBT of 15 C. Assuming no condensation to take place, the temperature of the mixture is approximately equal to:
a. 20 C
b. 22.5 C
c. 25 C
d. Cannot be found
Q. The temperature at which the water vapour in the air starts. condensing is known as
a. dew point
b. dry bulb
c. wet bulb
d. saturation
Q. When moisture is added to air at constant dry bulb temperature, the process is known as
a. Sensible cooling
b. humidification
c. dehumidification
d. Chilling
Q. Which of the following can be measured by a sling psychrometer?
a. Wet bulb temperature
b. Dry bulb as well as wet bulb temperatures
c. Specific humidity
d. Absolute humidity
Q. Which of the following refrigerant has the freezing point?
a. Ammonia
b. Carbondioxide
c. Freon 11
d. Freon 22
e. All of the above
Q. Dehumidification means
a. Removing humidity from a space
b. Reducing the quantity of water vapour in a space
c. Reducing the moisture content of a substance
d. Any of the above
e. None of the above
Q. In a refrigeration system a condenser
a. Receives liquid refrigerant and supplies liquid refrigerant
b. Receives vapour refrigerant and supplies vapour refrigerant
c. Receives vapour refrigerant and supplies liquid refrigerant
d. Receives liquid refrigerant and supplies liquid refrigerant
e. None of the above
Q. Dry ice is
a. Free from water
b. Free from dissolved air or gases
c. Does not contain impurities
d. Solidified form of carbondioxide
e. None of the above
Q. In halide torch test if there is leakage of refrigerant, the colour of flame with change to
a. Violet or orange
b. Red or pink
c. Blue or bright green
d. Black or grey
e. Yellow