Top 250+ Solved Refrigeration and Air conditioning MCQ Questions Answer
Q. In which part of the vapour compression cycle there is abrupt change in pressure and temperature
a. Drier
b. Solenoid valve
c. Expansion valve
d. The change is gradual throughout the cycle
e. Evaporator
Q. The ratio of sensible heat to total heat is known as
a. Relative humidity
b. Humidification ratio
c. Sensible heat factor
d. Specific humidity
e. Dew point
Q. The flow of the refrigerant in a refrigeration cycle is controlled by
a. Copper tubing
b. Compressor
c. Expansion valve
d. Evaporator
e. Condenser
Q. The refrigerant used for the air-conditioning of passenger aircraft cabin is
a. Air
b. Carbondioxide
c. Freon 11
d. Ammonia
e. Freon 12
Q. Under increased atmospheric pressure (as compared to the standard conditions) the steam will condense at
a. 100?C
b. More than 100?C
c. Depends on other conditions
d. Less than 100?C
e. Has nothing to do with pressure
Q. Which refrigerant has the highest critical point temperature?
a. Ammonia
b. Freon 11
c. Freon 12
d. Freon 22
e. None of the above
Q. The ratio of high temperature to low temperature for reversed Carnot refrigerator is 1.25. The COP will be
a. 2
b. 3
c. 4
d. 5
e. All of the above
Q. When the higher temperature is fixed, the COP of a refrigerating machine can be improved by
a. Operating the machine at higher speeds
b. Operating the machine at lower speeds
c. Raising the higher temperature
d. Lowering the higher temperature
e. None of the above
Q. A reversed Carnot cycle has a COP of 4. The ratio of higher temperature to lower temperature will be
a. 1.5
b. 2
c. 1.25
d. 2.5
e. None of the above
Q. A plate of vane used to direct or control movement of fluid or air within the confined area is known as
a. Baffle
b. Bellows
c. Regulator
d. Diffuser
e. None of the above
Q. The leaks of refrigerant from a cycle may be detected by
a. Halide torch test
b. Sulphur candle test
c. Soap and water test
d. Any of above
e. None of the above
Q. Super-conductors
a. Cannot be magnetised at low temperatures
b. Can be rubbed with other superconductors without frictional effects at low temperatures
c. Offer no resistance to flow of electricity at low remperatures
d. Offer no resistance to flow of heat at low temperatures
e. Offer no resistance to flow of fluids at low temperatures
Q. A desicant is
a. A process of removing heat under controlled conditions
b. A substance which reduces the viscosity of liquids
c. A solid substance capable of removing moisture from a gas, liquid or solid
d. Anammonia and a water solution
e. Heat given off by cargo
Q. A device designed to remove moisture from a refrigerant is called
a. Dehumidifier
b. Drier
c. Solenoid
d. Expansion valve
e. Humidstat
Q. The difference between wet and dry bulb temperatures
a. Increases at atmospheric temperature
b. Increases as air gets wet
c. Increases as air gets drier
d. remains constant always
e. None of the above