During a simple cooling process, atmospheric air with humidity ratio of 4.5 g vapor / kg dry air is cooled from 30 celcius to 20 celcius. what is the wet bulb temperature (celcius) of the cooled atmospheric air?

Answer: the wet bulb temp is approximately 13.15°c

Explanation: humidity ratio H varies directly with temperature (the hotter the air the more the moisture that vapourises into water vapour increasing the humidity ratio and vice versa)

H1T1 = H2T2

T is the temperatures (dry bulb)

H2 = (4.45 * 30) / 20 = 6.675 g/kg

We now have two properties of the second state (temp already given as 20°c) we check psychometric chart for the wet bulb temperature of that state which gives us approximately 13.15°c