11. R-12 has the __________ freezing point.
lowest
highest
✅ The correct answer is option A.
Heat Transfer, Refrigeration and Air Conditioning MCQs
12. The capacity of a domestic refrigerator is in the range of
0.1 to 0.3 TR
1 to 3 TR
3 to 5 TR
5 to 7 TR
✅ The correct answer is option A.
13. Air refrigerator works on
reversed Carnot cycle
Bell Coleman cycle
both (a) and ib)
none of these
✅ The correct answer is option C.
14. The heat of sun reaches to us according to
conduction
convection
radiation
none of these
✅ The correct answer is option C.
15. The material of pipe lines for a system using ammonia as a refrigerant should be copper.
Yes
No
✅ The correct answer is option B.
16. In order to cool and dehumidify a stream of moist air, it must be passed over the coil at a temperature
which lies between the dry bulb and wet bulb temperatures of the incoming stream
which lies between the wet bulb and dew point temperatures of the incoming stream
which is lower than the dew point temperature of the incoming stream
of adiabatic saturatio
✅ The correct answer is option C.
17. The expression Q = ρ AT4 is called
Fourier equation
Stefan-Boltzmann equation
Newton-Rikhmann equation
Joseph-Stefan equation
✅ The correct answer is option B.
18. In a vapour compression refrigeration system, a throttle valve is used in place of an expander because
it considerably reduces mass of the system
it improves the C.O.P., as the condenser is small
the positive work in isentropic expansion of liquid is very small
it leads to significan
✅ The correct answer is option C.
20. A vapour absorption refrigeration system
gives noisy operation
gives quiet operation
requires little power consumption
cools below 0° C
✅ The correct answer is option B.