Top 250+ Solved Refrigeration and Air conditioning MCQ Questions Answer
Q. In which section of a vapour compression system, the refrigerant is generally in the form of a wet vapour?
a. Condenser outlet
b. Expansion valve
c. Evaporator
d. Compressor
e. Condenser inlet
Q. In a vapour absorption system as compared to vapour compression system, the compressor is replaced by
a. Receiver
b. Expansion valve
c. Evaporator
d. Conderser
e. Absorber and generator
Q. If a one ton refrigeration machine, the significance of term "One ton" is that
a. One ton of water can be converted into ice
b. One ton of ice when melts from and at 0?C in 24 hours the refrigeration effect equivalent to that
c. One ton water can be stored at a time
d. One ton is the total weight of equipment
e. One ton of refrigerant is used
Q. The change in temperature resulting from a gas expanding from one constant pressure, with no heat transfer and no external work other than to maintain the constant pressure is known as
a. Dalton's law of partial pressures
b. Kinetic theory of gases
c. Avogadro's hypothesis
d. Joule - Thomoson effect
e. Law of conservation of energy
Q. Anhydrous substance is
a. Free of hydrogen and other chemicals containing hydrogen
b. Dry substance
c. Free of humidity
d. Free of hydrogen
e. Free of water especially water of crystallization
Q. No refrigerator using reversed Carnot cycle has been constructed because
a. It is uneconomical
b. It is less efficient
c. It requires bulky machines
d. 9.41
e. Isentropic portions of cycle require low speeds whereas isothermal protuons require high speeds
Q. The statement: If a maximum of gases or vapours is enclosed in a container, each will exert its own pressure on the container entirely independent of the others and the total absolute pressure will be equal to the sum of the partial pressure exerted by each of the gases. This statement is known as
a. Newton's law of gases
b. Kinetic theory of gases
c. Avogadro's hypothesis
d. Fick's law
e. Dalton's law of partial pressures.
Q. Defrosting of evaporators is done because
a. Frosting increases refrigerating effect
b. Frosting retards heat flow
c. Frosting is undersirable
d. Frosting obstructs flow of refrigerant
e. Frosting may cause damage to equipment
Q. No liquid can exist as a liquid at
a. 100?C
b. Zero pressure
c. Zero viscosity
d. 0?C
e. 10,000 m height above the surface of earth
Q. Dischloromono fluoroethane is
a. Freon 11
b. Freon 12
c. Freon 21
d. Freon 22
e. None of the above
Q. In a refrigeration system, if the compressor short cycles, the probable cause could be
a. Intermittent contact in electric control circuit
b. Dirty or iced evaporator
c. Lack of refrigerant
d. Overchange of refrigerant
e. Any of the above
Q. Reversed Carnot cycle assumes that all processes in the cycle are
a. Non-flow only
b. 10,000 m height above the surface of earth
c. Transient flow
d. Non flow or steady flow
e. Steady flow only
Q. Which of the following valves is used on domestic refrigerators
a. Solenoid valve
b. Expansion valve
c. Spring safety valve
d. Wheel valve
e. None of the above
Q. A thermometer installed, in a vapour compression ammonia system, after the condenser shows elevated reading than the normal. It shows that
a. Condenser needs cleaning
b. Cooling tower or spray pond not handling the load properly
c. Uneven water distribution over the condensing surfaces
d. Any of the above
e. None of the above