99. The most suitable refrigerant for a commercial ice plant is
A.Hrine
B.NH3
C.Freon
D.Air
100. Leaks in brine system can be detected by
A.Halide torch which on detection produces greenish flame lighting
B.Sulphur sticks which on detection give white smoke
C.Using reagents
D.Smelling
101. Big refrigeration plants (of capacity of the order of 1000 tons) usually employ following type of refrigeration plant
A.Vapour absorption
B.Vapour compression
C.Air cycle
D.Electrolux refrigerator
102. For ammonia system, the pipe should be of following material
A.Brass
B.Copper
C.Cast steel or wrought iron
D.Aluminium
103. In an atmospheric cooling tower, the temperature of the circulating water can be reduced to
A.10-15? above surrounding atmosphere
B.Equal to surrounding atmosphere
C.10-15? below surrounding atmosphere
D.50-60? below surrounding atmosphere
104. If ice in a plant is made at ? 6?C and if temperature difference between ice and refrigerant is 5?C, then refrigerant temperature is
A.? 1?C
B.0?C
C.11?C
D.? 6?C
105. The refrigerant is never filled to more than 80% of the rated capacity while refilling the refrigerant cylinder because
A.To avoid refrigerant decomposition
B.The cylinder would be too heavy for easy handling
C.The 20% vapour space provides a safety margin for liquid expansion when the surrounding temperature rises
D.The cylinders would become top heavy if filled 100% and tend to fall from the upright position
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