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is it because of heat capacity?


kenny1999

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I am living in a subtropical region and we are in summer now. Every time when I come out from a hot bath (I never bath with cool water) and before I dry my body, I feel quite cool, but room temperature at night is still over 85 F. Is it because of the high heat capacity of water droplets on my body which has absorbed heat around my skin?

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25 minutes ago, kenny1999 said:

I am living in a subtropical region and we are in summer now. Every time when I come out from a hot bath (I never bath with cool water) and before I dry my body, I feel quite cool, but room temperature at night is still over 85 F. Is it because of the high heat capacity of water droplets on my body which has absorbed heat around my skin?

Your hot water is hopefully set for at least 120 F (bacteria issues), which you're probably mixing with a little cold water to bring the bath to around 100 F. You spend some time adjusting to that so when you get out, 85 F feels quite cool. Also, before you dry off, water droplets are evaporating, drawing energy as they change from liquid to gas, which causes the cooling on the surface of your skin. 

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I use evaporation a lot when the weather gets uncomfortably hot. A/C isn't worth installing in the UK, but you do get a few days or weeks of discomfort in the summer. 

I wear very little, and spray myself now and then with water, or have a wipe over with a damp towel. It's super-effective, and no effort or cost. 

It's the evaporation that works for quite a while, much longer than the cold of the water. 

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1 hour ago, kenny1999 said:

I am living in a subtropical region and we are in summer now. Every time when I come out from a hot bath (I never bath with cool water) and before I dry my body, I feel quite cool, but room temperature at night is still over 85 F. Is it because of the high heat capacity of water droplets on my body which has absorbed heat around my skin?

Not heat capacity but Latent Heat of Vaporisation of water, i.e. the heat absorbed in turning liquid water into vapour. This is very high for water, due mainly to the need to break hydrogen bonding between water molecules as they break away from the liquid.

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It's the latent heat (as exchemist notes) combined with low humidity. If the humidity is high the water doesn't evaporate readily (you get significant condensation, which cancels the effect to some extent)

In places in the US where you have low humidity, such as the southwest, they use evaporative cooling systems, aka "swamp coolers" 

https://home.howstuffworks.com/home-improvement/heating-and-cooling/swamp-cooler.htm

Not so useful in muggy areas

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