The saturation temperature of water vapour at its partial pressure is equal to
Wet bulb temperature
Dew point temperature
Adiabatic saturated temperature
Dry bulb temperature
The moisture content of air is indicated by
Wet bulb temperature and dew point temperature
Wet bulb temperature and dry bulb temperature
Adiabatic saturation temperature and dew point temperature
Enthalpy and wet bylb temperature
The wet bulb temperatue is a measure of
Absolute humidity
Specific humidity
Relative humidity
Degree of saturation
When the dry bulb and wet bulb temperature of air are same, then relative humidity of air will be
Zero percent
50 per cent
66.7 per cent
100 per cent
A 100 per cent relative humidity of air implies that
Wet bulb temperature equals the dew point temperature
Dew point temperature equals the saturation temperature
Saturation temperature equals the dry bulb temperature
Dry bulb, wet bulb , dew point and saturation temperatures are equal
Which of the followings is not a correct statement?
Condensation of moisture begins at the dew point
Upon cooling the saturated air, the moistures seqarates out and the air becomes foggy or misty
Higher the relative humidity, greater will be the wet bulb depression
Regardless of temperature the values of relative humidity and degree of saturation are identical both for saturated air and dry air
The partial pressure of water vapour in a certain sample of air-water vapour mixture at its dry bulb temperature and dew point temperature are stated to be 0.0563 bar and 0.0234 bar respectively. If atmospheric pressure equals 1.0132 bar, then
1)the relative humidity is approximately
2)the degree of saturation is
0.29, 0.28
0.41, 0.40
0.71, 0.73
0.96, 0.92
A sling psychrometer can measure
Absolute humidity
Specific humidity
Wet bulb temperature
Dry as well as wet bulb temperature
Consider the following statements:
A psychrometer measures
(1) wet bulb temperature
(2) dry bulb temperature
(3) dew point temperature
which of these statements are correct?
1 alone
1 and 2
2 and 3
1, 2 and 3
All of the following statements are correct, except
Wet bulb temperature is an indirect measure of the moisture content of air
Wet bulb temperature is a thermodynamic property
During measurement of wet bulb temperature by a sling psychrometer, the air velocity around the wick is kept 5-10m/s
Under conditions of 100 per cent relative humidity, the wet bulb depression is zero
Which of the following parameters cannot be calculated theoretically (using steam table and Dalton’s law of partial pressure) from known values of dry bulb temperature and relative humidity?
Partial pressuer of water vapour
Dew point temperature
Wet bulb temperature
Humidity ratio
/
1, 2 only
2, 3 only
1, 2 and 4
All
Which parameters are the independent variables in the construction of psychometric plot for a particular value of barometric pressure?
Dry bulb temperature and specific humidity
Wet bulb temperature and relative humidity
Dry bulb temperature and wet bulb temperature
Dry bulb temperature and enthalpy
In a psychrometric chart, the vertical lines parallel to the ordinate indicate
Dry bulb temperature
Wet bulb temperature
Specific humidity
Enthalpy of saturation
The uniformly spaced horizontal lines running parallel to the abscissa in a psychrometric chart indicate
Absolute humidity
Specific humidity
Dew point temperature
Volume
On a psychrometric chart, the relative humidity lines are represented by
Uniformly spaced horizontal lines
Uniformaly speed inclined lines
Non-uniformly spaced inclined lines
Curved lines
The constant wet bulb lines are non-uniformly spaced and inclined slping down towards the right of psychrometric diagram and follow very closely the lines of
Constant volume
Constant relative humidity
Constant enthalpy
Constant moisture content
To fix the state point in respect of air vapour mixtures, three intrinsic properties are needed. Yet, the psychrometric chart requires only two because
The mixture can be treated as a perfect gas
The water vapour is in the superheated state
The chart is an approximation to true valves
The chart is drawn for a fixed pressure
Which is not true in the context of sensible cooling achieved by passing the air over a surface that is at a temperature less than the dry bulb temperature but greater than the dew point temperature?
Wet bulb and dew point temperatures decrease
No change in specific humidity
Relative humidity increases
No condensation of vapour
During sensible cooling of air, its wet bulb temperature ………and dew point ………
Increases, remains constant
Decreases, remains constant
Increases, decreases
Decreases, increases