50. A certain refrigerating system has a normal operating suction pressure of 10 kg/cm2 gauge and condensing pressure of about 67 kg/cm2. The refrigerant used is
A.Ammonia
B.Carbon dioxide
C.Freon
D.Brine

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51. Aqua anunonia is used as refrigerant in the following type of refrigeration system (a) compression (b) direct
A.(c) indirect
B.(d) absorption
C.(e) none of the above
D.7.60. If the evaporator temperature of a plant is lowered, keeping the condenser temperature constant, the h.p. of compressor required will be

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52. If the evaporator temperature of a plant is lowered, keeping the condenser temperature constant, the h.p. of compressor required will be
A.Same
B.More
C.Less
D.More/less depending on rating

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53. In a refrigeration cycle, the flow of refrigerant is controlled by
A.Compressor
B.Condenser
C.Evaporator
D.Expansion valve

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54. Where does the lowest temperature occur in a vapour compression cycle ?
A.Condenser
B.Evaporator
C.Compressor
D.Expansion valve

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55. The leaks in a refrigeration system using Freon are detected by
A.Halide torch which on detection produces greenish flame lighting
B.Sulphur sticks which on detection gives white smoke
C.Using reagents
D.Smelling

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56. rick up the incorrect statement
A.Lithium bromide used in vapour absorption cycle is nonvolatile
B.Lithium bromide plant can't operate below 0?C
C.A separator is used in lithium bromide plant to remove the unwanted water vapour by condensing
D.Concentration of solution coming out of lithium bromide generator is more in comparison to that entering the generator

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