Degrees of Freedom Analysis in Steady-State Process

Question 1
Marks : +2 | -2
Pass Ratio : 100%
What is the work of the humidification process?
Vaporization
Freezing
Condensing
None of the mentioned
Explanation:
Humidification vaporizes liquid water to moist air.
Question 2
Marks : +2 | -2
Pass Ratio : 100%
Enthalpy of air is 15 J and enthalpy of water vapor is 20 J, if the total enthalpy of the system is 20 J, what is the humidity of the system?
25%
50%
75%
100%
Explanation:
20 = 15 + 20*H, => H = 0.25 = 25%.
Question 3
Marks : +2 | -2
Pass Ratio : 100%
In air conditioning process, what has to be done first to the moist air?
Heating
Cooling
Heating & Cooling
None of mentioned
Explanation:
In air conditioning process, moist air is heated and then cooled.
Question 4
Marks : +2 | -2
Pass Ratio : 100%
In condensation, moist air is cooled below its which temperature?
Dew-point temperature
Dry-bulb temperature
Wet-bulb temperature
Saturation temperature
Explanation:
In condensation, moist air is cooled below its saturation temperature.
Question 5
Marks : +2 | -2
Pass Ratio : 100%
What is added to the moist air in the combustion process?
Water
Carbon dioxide
Oxygen
None of the mentioned
Explanation:
Water is added to the moist air in the combustion process.
Question 6
Marks : +2 | -2
Pass Ratio : 100%
Enthalpy of air is 15 J and enthalpy of water vapor is 20 J, if the total enthalpy of the system is 25 J, what is the humidity of the system?
10%
50%
100%
200%
Explanation:
25 = 15 + 20*H, => H = 0.5, => H = 50%.
Question 7
Marks : +2 | -2
Pass Ratio : 100%
Enthalpy of air is 10 J and enthalpy of water vapor is 15 J, if the total enthalpy of the system is 25 J, what is the humidity of the system?
20%
50%
100%
180%
Explanation:
25 = 10 + 15*H, => H = 1, => H = 100%.
Question 8
Marks : +2 | -2
Pass Ratio : 100%
Enthalpy of air is 20 J and enthalpy of water vapor is 6 J, if the total enthalpy of the system is 23 J, what is the humidity of the system?
10%
20%
40%
50%
Explanation:
23 = 20 + 6*H, => H = 0.5, => H = 50%.
Question 9
Marks : +2 | -2
Pass Ratio : 100%
Enthalpy of air is 5 J and enthalpy of water vapor is 10 J, if the total enthalpy of the system is 25 J, what is the humidity of the system?
50%
100%
150%
200%
Explanation:
25 = 5 + 10*H, => H = 2, => H = 200%.
Question 10
Marks : +2 | -2
Pass Ratio : 100%
What is the work of drying process?
Decreases the moisture content
Vaporizes water
Increases the moisture content
None of the mentioned
Explanation:
Drying decreases the moisture content of air.