Top 250+ Solved Refrigeration and Air conditioning MCQ Questions Answer
Q. Moisture in Freon refrigeration system causes
a. Ineffective refrigeration
b. Damage to compressor
c. High power consumption
d. Freezing of automatic regulating valve
e. None of the above
Q. Which of the following is not a desirable property of a refrigerant?
a. High critical temperature
b. Low specific heat of liquid
c. Low boiling point
d. High specific volume of air
e. All of the above
Q. A Carnot refrigerator operates between 300.3 K and 273 K. The fraction of cooling effect required as work input is
a. 20%
b. 10%
c. 50%
d. Not possible to find with the data
e. All of the above
Q. A thermometer in the compressor discharge line
a. Confirms the flow of refrigerant
b. Indicates the efficiency of cycle
c. Helps in adjusting the compressor performance
d. Shows the heat of refrigerant leaving the cylinder on way to the condenser
e. None of the above
Q. Freon 12 is a compound consisting of stoms of
a. Carbon, hydrogen and fluorine
b. Carbon and hydrogen
c. Carbon, hydrogen, fluorine and chlorine
d. Carbon, fluorine and chlorine
e. Carbon, hydrogen and oxygen
Q. During sensible of cooling of air
a. Wet bulb temperature decreases and relative humidity increases
b. Both wet bulb temperatures as well as relative humidity increase
c. Both humidity ratio as well as relative humidity remain constant
d. Both wet bulb temperature as well as relative humidity decrease
e. Wet bulb temperatures increases and relative humidity decreases
Q. The type of compressor used in refrigeration system is
a. Reciprocating
b. Centrifugal
c. Rotary sliding vane
d. Rotary screw compressor
e. All of the above
Q. In a refrigeration cycle the heat is rejected by refrigerant at
a. Evaporator
b. Condenser
c. Expansion valve
d. Compressor
e. All of the above
Q. An average adult while sitting in a cinema hall
a. Discharges about 100 kcal of heat per hour
b. Discards about 500 kcal of heat per hour
c. Absorbs about 500 kcal of heat per hour
d. Neither absorbs nor discards heat
e. Absorbs about 100 kcal of heat per hour
Q. During compression in a vapour compression cycle of the refrigerant is super heated
a. C.O.P. is reduced
b. C.O.P. is increased
c. Work done is reduced
d. Refrigerating effect is reduced
e. None of the above
Q. The heat removed capacity of a one ton refrigerator is
a. 100 kcal/4 hour
b. 100 kcal/hour
c. 50 kcal/min
d. 25 kcal/sec
e. None of the above
Q. A prssure gauge on the discharge side of compressor
a. Is mounted for show only
b. Indicates the temperature of refrigerant after compression
c. Gives a warning when the pressure reaches a dangerous point
d. Gives an ideas about the coefficient of performance of the cycle
e. Confirms the flow of refrigerant in cycle
Q. Major modification required to produce temperature of - 200?C in a vapour compression refrigeration system using Freon 12 as refrigerant, is
a. Condenser capacity must be increased to handle the refrigerant
b. Size of compressor required would be large to handle volumes of vapour
c. Compression ratio has to be restricted till stronger body of compressor is needed
d. Freon 12 cannot be used for such low temperatures
e. Insulation should be capable of withstanding such low temperatures
Q. In a vapour absorption refrigeration system the power is required for vapour compressor as compared to that in vapour compression cycle is
a. More
b. Less
c. There is no such relation
d. One forth
e. Half