51. The inclined and non-uniformly spaced straight lines on a psychrometric chart indicates wet bulb temperature.
Agree
Disagree
✅ The correct answer is option A.
Heat Transfer, Refrigeration and Air Conditioning MCQs
52. The relative coefficient of performance is equal to
Actual C.O.P. x Theoretical C.O.P.
none of these
✅ The correct answer is option B.
53. A valve which maintains a constant degree of superheat at the end of the evaporator coil, is called
automatic expansion valve
high side float valve
thermostatic expansion valve
low side float valve
✅ The correct answer is option D.
54. Wet bulb temperature indicates the moisture content in air.
Agree
Disagree
✅ The correct answer is option A.
55. The space between the two walls of a thermos flask is evacuated because vacuum is a __________ conductor of heat.
good
bad
✅ The correct answer is option B.
56. The minimum temperature to which water can be cooled in a cooling tower is
dew point temperature of air
wet bulb temperature of air
dry bulb temperature of air
ambient air temperatur
✅ The correct answer is option B.
57. In air-conditioning of aeroplanes, using air as a refrigerant, the cycle used is
reversed Carnot cycle
reversed Joule cycle
reversed Brayton cycle
reversed Otto cycle
✅ The correct answer is option C.
58. During dehumidification process, the relative humidity
remains constant
increases
decreases
✅ The correct answer is option C.
59. Which of the following refrigerant is highly toxic and flammable?
Ammonia
Carbon dioxide
Sulphur dioxide
R-12
✅ The correct answer is option A.
60. The freezing point of R-12 is
-86.6°C
-95.2°C
-107.7°C
-135.8°C
✅ The correct answer is option D.