Question

why do we feel cool when sweat dries

Answer 1

we feels cool when our sweat evaporate because when it evaporates then it produce latent heat ,it is the heat which change the state of matter.
so sweat change from liquid to vapour by latent heat so in doing this latent heat require a heat so it takes heat from our body and we feel cool

Answer 2

Due to evaporation as evaporation causes cooling . As evaporation is directly proportional to humidity and humidity causes sweat by Aniket 7th IITF genius