রেফ্রিজারেশন এন্ড এয়ারকন্ডিশনিং MCQ
41. The higher temperature in compression cycle occurs at-
receiver
expansion valve
evaporator
compressor discharge
42. Which of the following cycles uses air as the refrigerant?
Ericsson
Carmot
Stirling
Bell-coleman
43. A domestic refrigerator has the co- efficient of performance-.
equal to 10
less than 10
more than 10
none
44. One of the purposes of subcooling the liquid refrigerant is to-
reduce compressor overheating
reduce compressor discharge temperature
increase cooling effect
ensure that only liquid and not the vapour enters the expansion (throttling) valve
45. Absorption system normally uses the following refrigerant-
Freon-11
ammonia
Freon-22
CO
46. Which of the following refrigerant is highly toxic and flammable?
sulphur dioxide
Freon-12
Ammonia
Carbon dioxide
47. Air refrigeration operates on—
Carnot cycle
Rankine cycle
Reversed Carnot cycle
Brayton cycle
48. In refrigerator, liquid receiver is required between condenser and flow controlling device, if quantity of refrigerant for system is-
less than 2kg
more than or equal to 3.65kg
more than 10kg
there is no such consideration
49. Highest temperature refrigeration cycle should be encountered In near critical temperature of refrigerant--
above critical temperature
at critical temperature
much below critical temperature
none
50. The relative coefficient of performance is-
actual COP/theoretical COP
theoretical COP/actual COP
actual COP x theoretical COP
1-actual COP x theoretical COP
51. A standard ice point temperature corresponds to the temperature of-.
water at 0°C
ice at-4°C
solid and dry ice
mixture of ice and water under equilibrium conditions
52. Air refrigeration cycle is used in--
domestic refrigerators
commercial refrigerators
air-conditioning
gas liquefaction
53. Ammonia-absorption refrigeration cycle requires--
very litle work input
maximum work, input
nearly same work input as for vapour
compression cycle zero work input
54. Vapour compression refrigeration is some what like-.
Camot cycle
Rankine cycle
reversed Canet cycle
none of the above
55. During a refrigeration cycle heat is rejected by the refrigerant in a-
compressor
condenser
evaporator
expansion valve
56. The bank of tubes at the back of domestic refrigerator are-
condenser tubes
evaporator tubes
refrigerant cooling tubes
capillary tubes
57. Domestic refrigerator working on vapour compression cycle uses the following type of expansion device-
electrically operated throttling valve
manually operated valve
thermostatic valve
capillary tube
58. Presence of moisture in a refrigerant affects the working of--
compressor
condemer
evaporator
expansion valve
59. Refrigeration in aeroplanes usually employs the following refrigerant-
Freon-11
Air
Freon-22
Ammonia
60. For better COP of refrigerator, the pressure range corresponding to temperature in evaporator and condemer must be-
small
equal
high
anything