260 Important Refrigeration And Air Conditioning MCQ Question and Answer | PDF Free Download
1.The dry bulb temperature lines, on the psychrometric chart are
- AVertical and uniformly spaced
- BHorizontal and uniformly spaced
- CHorizontal and non-uniformly spaced
- DCurved lines
2.In Electrolux refrigerator
- AAmmonia is absorbed in hydrogen
- BAmmonia is absorbed in water
- CAmmonia evaporates in hydrogen
- DHydrogen evaporates in ammonia
3.For obtaining high COP, the pressure range of compressor should be
- AHigh
- BLow
- COptimum
- DAny value
4.The pressure at the outlet of a refrigerant compressor is called
- ASuction pressure
- BDischarge pressure
- CCritical pressure
- DBack pressure
5.The pressure at the inlet of a refrigerant compressor is called
- ASuction pressure
- BDischarge pressure
- CCritical pressure
- DBack pressure
6.In a saturated air-water vapour mixture, the
- ADry bulb temperature is higher than wet bulb temperature
- BDew point temperature is lower than wet bulb temperature
- CDry bulb, wet bulb and dew point temperature are same
- DDry bulb temperature is higher than dew point temperature
7.The conditioned air supplied to the room must have the capacity to take up
- ARoom sensible heat load only
- BRoom latent heat load only
- CBoth room sensible heat and latent heat loads
- DNone of the above
8.A reversible engine has ideal thermal efficiency of 30%. When it is used as a refrigerating machine with all other conditions unchanged, the coefficient of performance will be
- A1.33
- B2.33
- C3.33
- D4.33
9.A refrigerant compressor is used to
- ARaise the pressure of the refrigerant
- BRaise the temperature of the refrigerant
- CCirculate the refrigerant through the refrigerating system
- DAll of the above
10.In a flooded evaporator refrigerator, an accumulator at suction of compressor is used to
- ACollect liquid refrigerant and prevent it from going to compressor
- BDetect liquid in vapour
- CSuperheat the vapour
- DCollect vapours
11.The temperature of ammonia after compression in a vapour compression system is
- A20 to 50°C
- B50 to 70°C
- C70 to 110°C
- DNone of these
12.The condition of refrigerant as it leaves the compressor in a vapour compression system is
- ASaturated liquid
- BWet vapour
- CDry saturated vapour
- DSuperheated vapour
13.Chaperon equation is applicable for registration at
- ASaturation point of vapour
- BSaturation point of liquid
- CSublimation temperature
- DTriple point
14.The coefficient of performance of Electrolux refrigerator is the ratio of
- AHeat supplied by the gas burner to the heat absorbed by the evaporator
- BHeat absorbed by the evaporator to the heat supplied by the gas burner
- CHeat supplied by the gas burner minus the heat absorbed by the evaporator to the heat supplied by the gas burner
- DHeat absorbed by the evaporator minus the heat supplied by the gas burner to the heat absorbed by the evaporator
15.Formation of frost on evaporator in refrigerator
- AResults in loss of heat due to poor heat transfer
- BIncreases heat transfer rate
- CIs immaterial
- DCan be avoided by proper design
16.A valve which maintains a constant degree of superheat at the end of the evaporator coil, is called
- AAutomatic expansion valve
- BHigh side float valve
- CThermostatic expansion valve
- DLow side float valve
17.The refrigerant after condensation process is cooled below the saturation temperature before throttling. Such a process is called
- ASub-cooling or under-cooling
- BSuper-cooling
- CNormal cooling
- DNone of these
18.Aqua ammonia is used as refrigerant in the following type of refrigeration system
- ACompression
- BDirect
- CIndirect
- DAbsorption
19.A thermostatic expansion valve in a refrigeration system
- AEnsures the evaporator completely filled with refrigerant of the load
- BIs suitable only for constant load systems
- CMaintains different temperatures in evaporator in proportion to load
- DNone of the above
20.A refrigeration system
- ARemoves heat from a low temperature body and delivers it to a high temperature body
- BRemoves heat from a high temperature body and delivers it to a low temperature body
- CRejects energy to a low temperature body
- DNone of the above