Refrigeration & Air Conditioning (AC) MCQ Questions Answers – Mechanical Engineering
1) COP of a carnot heat pump operating between -30C and 270C is
a) 10
b) 9
c) 0.111
d) 0.10
2)Which is the primary refrigerant in central air conditioning plant
(a) Air
(b) Water
(c) Freon-22
(d) None
(Ans:c)
3) One tones of refrigeration is equal to
a) 210 kJ/min
b) 3.5 kJ/min
c) 105 KJ/min
d) 250 kJ/min
4)Which is the secondary refrigerant in an ice plant
(i) Mercury
(j) Brine solution
(k) Freon-22
(l) None
(Ans:b)
5) Which is usually the costliest item in a refrigeration system ?
a) Condenser
b) Capillary tube
c) Compressor
d) Evaporator
6)Latent heat is highest for
(a) Refrigerant – 22
(b) Ammonia
(c) Water
(d) None
(Ans:c)
7) An Electrolux refrigerator uses
a) one pump
b) two pump
c) no pump
d) three pump
8) The ideal gas-refrigeration cycle is similar to
Brayton cycle
b. Reversed Brayton cycle
c. Rankine cycle
d. Reversed Rankine cycle
ans – b
9) A carnot refrigerator has a COP of 6. What is the ratio of the lower to the higher absolute temperature
a) 1/6
b) 7/8
c) 6/7
d) 1/7
10)For the same capacity of plant, the COP of the vapour absorption refrigeration system is
lower than the COP of the vapour compression refrigeration system
b. higher than the COP of the vapour compression refrigeration system
c. same as the COP of the vapour compression refrigeration system
d. cannot say
ans – a