MCQ on Refrigeration and Airconditioning for JE Exam Part 5
41. A refrigerator working on a reversed carnot
cycle has a COP of 4. If it works as heat pump
and consumes 1kW, the heating effect will be:
(a) 1kW
(c) 5kW
42. In a refrigeration system the refrigerant gain
heat at :
(a) Compressor
(b) Condenser
(c) Expansion valve
(d) Evaporator
Ans : (d)
43. The throttling operation in a refrigeration
cycle is carried out in :
(a) Evaporator
(b) Discharge valve
(c) Capillary tube
(d) Expansion valve
Ans : (d)
44. The chemical formula of Freon- 12 is :
Ans : (c)
45. In mechanical refrigeration system, the
refrigerant has the maximum temperature :
(a) before expansion valve
(b) between compressor and condenser
(c) between condenser and evaporator
(d) between compressor and evaporator
Ans : (b)
46. A simple saturated refrigeration cycle has the
following state points. Enthalpy after
compression = 425 kJ/kg ; enthaly after
throttling = 125 kJ/kg ; enthalpy before
compression = 375 kJ/ kg. The COP of
refrigeration is :
(a) 5
(b) 3.5
(c) 6
(d) not possible to find with this data
47. If the capacity of a refrigerating machine is one
ton, then the rate of heat abstraction is equal to :
Ans : (a)
48. Which of the following in given option is
correct by matched. The Boiling point of Refrigerants are given in
list-I and List-II
49. 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) Cannot be calculated
Ans : (b)
50. Aircraft refrigeration system is based upon–
(a) Joule cycle
(b) Brayton cycle
(c) Carnot cycle
(d) Vapour compression cycle
Ans : (b)
| (b) (d) | 4kW 6kW |
42. In a refrigeration system the refrigerant gain
heat at :
(a) Compressor
(b) Condenser
(c) Expansion valve
(d) Evaporator
Ans : (d)
43. The throttling operation in a refrigeration
cycle is carried out in :
(a) Evaporator
(b) Discharge valve
(c) Capillary tube
(d) Expansion valve
Ans : (d)
44. The chemical formula of Freon- 12 is :
| (a) CCl F2 (c) CCl2 F2 | (b) CCl2 F3 (d) CCl F |
45. In mechanical refrigeration system, the
refrigerant has the maximum temperature :
(a) before expansion valve
(b) between compressor and condenser
(c) between condenser and evaporator
(d) between compressor and evaporator
Ans : (b)
46. A simple saturated refrigeration cycle has the
following state points. Enthalpy after
compression = 425 kJ/kg ; enthaly after
throttling = 125 kJ/kg ; enthalpy before
compression = 375 kJ/ kg. The COP of
refrigeration is :
(a) 5
(b) 3.5
(c) 6
(d) not possible to find with this data
47. If the capacity of a refrigerating machine is one
ton, then the rate of heat abstraction is equal to :
| (a) 50kcal/min | (b) | 100kacl/min |
| (c) | 150kcal/min |
| (d) | 500kcal/min |
48. Which of the following in given option is
correct by matched. The Boiling point of Refrigerants are given in
list-I and List-II
| (a) R – 12 (b) NH3 (c) R 134 a (d) R 22 | – 29.8°C – 33.35°C – 24.15°C – 40.8°C |
| Ans : (c) |
K and 273 K. The fraction of cooling effect
required as work input is–
(a) 20%
(b) 10%
(c) 50%
(d) Cannot be calculated
Ans : (b)
50. Aircraft refrigeration system is based upon–
(a) Joule cycle
(b) Brayton cycle
(c) Carnot cycle
(d) Vapour compression cycle
Ans : (b)