# Cool air on sweat

When my face is full of sweat, I go near the A.C. and when the cool air touches my sweat it feels colder than dry parts? Why does the sweat feel colder than dry parts?

• Because it evaporates and removes heat from your body. – orthocresol Sep 8 '17 at 15:04
• Sweat is supposed to cool you down and has been evolutionarily ‘designed’ and kept that way. – Jan Sep 9 '17 at 7:28

The heat of evaporation of the water is $\pu{2260J/g}$. That means for every one gram of water, it takes $\pu{2260J}$ of energy to vaporize it. The water (evaporating) takes the needed heat energy from your $\pu{37 ^\circ C}$ body.