What is the Science Behind Wet-Bulb Temperature and Evaporative Cooling?

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Wet-bulb temperature is influenced by evaporative cooling, where evaporation removes high-kinetic-energy molecules from water, leading to a decrease in temperature. This process creates a temperature difference between wet and dry thermometers, which can exceed 10°C in real environments. The significant temperature difference indicates that water and air do not reach thermal equilibrium until all the water evaporates. The discussion emphasizes understanding the molecular and practical implications of this phenomenon rather than the mathematical equations involved. Overall, evaporative cooling plays a crucial role in temperature regulation in various environmental conditions.
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Homework Statement


Imagine a wet thermometer whose bulb is covered with a wet wick at 1 atm. Temperature of the water happens to drop during the process of evaporation.

Homework Equations


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The Attempt at a Solution


Does evaporation lower the temperature of water just by removing high-kinetic-energy molecules and lowers it's temperature, just so there can be a driving force for heat transfer? So basically heat from the air is supplied to the water resulting in lowering it's temperature by some small amount?

Somewhere I read that temeprature difference between wet and dry thermometer goes up to 10°C, or more. It's sort of shocking to me, does that mean that water and air at differ by that large amount in a real environment? So they are basically never in a thermal equilibrium until all water evaporates? Wow...

I'm not really interested in math behind it, i just don't get what's going on in molecular, practical level.
 
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