64. Superheating in a refrigeration cycle
A.Increases COP
B.Decreases COP
C.COP remains unaltered
D.Other factors decide COP
65. The suction pipe diameter of refrigerating unit compressor in comparison to delivery side is
A.Bigger
B.Smaller
C.Equal
D.Smaller/bigger depending on capacity
66. Moisture in freon refrigeration system causes
A.Ineffective ref5ig'eration
B.High power consumption
C.Freezing automatic regulating valve
D.Corrosion of whole system
67. The advantage of dry compression is that
A.It permits higher speals to be used
B.It permits complete evaporation in the evaporator
C.It results in high volumetirc and mechanical efficiency
D.All of the above
68. Choose the wrong statement
A.Temperature of medium being cooled must be below that of the evaporator
B.Refrigerant leaves the condenser as liquid
C.All solar thermally operated absorption systems are capable only of intermittent operation
D.Frost on evaporator reduces heat transfer
69. Under-cooling in a refrigeration cycle
A.Increases COP
B.Decreases COF
C.COP remains unaltered
D.Other factors decide COP
70. For obtaining high COP, the pressure range of compressor should be
A.High
B.Low
C.Optimum
D.Any value
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