Mechanical Engineering - Heat Transfer, Refrigeration and Air Conditioning

16.
Thermal conductivity of solid metals __________ with rise in temperature.
remains same
decreases
increases
Answer: Option
Explanation:
No answer description is available. Let's discuss.

17.
The horizontal and non-uniformly spaced lines on a psychrometric chart indicates
dry bulb temperature
wet bulb temperature
dew point temperature
specific humidity
Answer: Option
Explanation:
No answer description is available. Let's discuss.

18.
A reversible engine has ideal thermal efficiency of 30%. When it is used as a refrigerating machine with all other conditions unchanged, the coefficient of performance will be
1.33
2.33
3.33
4.33
Answer: Option
Explanation:
No answer description is available. Let's discuss.

19.
Which of the following refrigerant is highly toxic and flammable?
Ammonia
Carbon dioxide
Sulphur dioxide
R-12
Answer: Option
Explanation:
No answer description is available. Let's discuss.

20.
The unit of Stefan-Boltzmann constant is
Watt/mK
Watt/m2K2
Watt/m2K4
Watt/mK2
Answer: Option
Explanation:
No answer description is available. Let's discuss.