Mechanical Engineering - Heat Transfer, Refrigeration and Air Conditioning
Exercise :: Heat Transfer, Refrigeration and Air Conditioning - Section 5
41.
The ratio of actual mass of water vapour in a given volume of moist air to the mass of water vapour in the same volume of saturated air at the same temperature and pressure, is called
A.
humidity ratio B.
relative humidity C.
absolute humidity D.
degree of saturation
Answer: Option B
Explanation:
42.
The transfer of heat by molecular collision is smallest in
A.
solids B.
liquids C.
gases D.
none of these
Answer: Option C
Explanation:
43.
During dehumidification process, the relative humidity
A.
remains constant B.
increases C.
decreases
Answer: Option C
Explanation:
44.
The space between the two walls of a thermos flask is evacuated because vacuum is a __________ conductor of heat.
Answer: Option B
Explanation:
45.
The ratio of actual heat transfer to the maximum possible heat transfer is known as heat exchanger effectiveness.
Answer: Option A
Explanation: