Determination Of Relative Humidity By Wet And Dry Bulb Hygrometer
Name of Expt.:
Determination Of Relative Humidity By Wet And Dry Bulb Hygrometer.
To find out the temperature and relative humidity of lab room
Relative humidity = actual vapour pressure/standard vapour pressure.
An alternative definition for relative humidity is the ratio of the absolute humidity of the air to that of air saturated with water vapour at the same temperature and pressure. This ratio is also expressed as a percentage.
Wet and dry bulb hygrometer.
- At first , we take a wet and dry bulb hygrometer.
- Then we take a reading of wet bulb thermometer and a reading of dry bulb thermometer
- Then we find out the difference of dry and wet bulb thermometer reading
- Then we bet up the value of temperature difference between wet and dry bulb thermometer by rotating berew of R. H. Scale.
- Then we determine the value of relative humidity with respect to dry bulb thermometer.
- We repeat in 10 times
Dry bulb reading=
Wet bulb reading=
R.H. % from table=
Mean R.H. = ( 76+70+65+70+76+70+76+70+70+76 ) / 10
= 71.9 %
As our testing lab is not air conditioned so the dry bulb hygrometer is of course need for the accurate of all expects. Moreover it is the most common hygrometer and easily usable.