Naked Science Forum
General Science => General Science => Topic started by: neilep on 10/08/2009 14:15:04
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Dearest Special Peeps Of Academic Overtures,
As a sheepy I of course luff being wet. Representing the UK in all types of watersports has been my forte.
One thing I notice though when I come out the shower or bath is that I then feel very cold:
Look here's a hand that is wet !
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A Wet Hand Being Not Dry
Nice eh ? the right one being delivered on Tuesday to make a matching pair (ewe can only guess how I held the camera !)
Now I used nice warm water to wet this hand and so the water must now be my body temperature at the least yes ?
so, why does my hand feel so cold when wet ?
If ewe can help me know this I will lend ewe this hand.
hugs & shmishes
mwah !
Neil
Marti Pellow Has a Lovely Smile
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Because of water vaporization: the process requires heat, and it takes it from your skin. If water couldn't vaporize, because air's humidity is at 100%, you won't feel any cold.
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Because of water vaporization: the process requires heat, and it takes it from your skin. If water couldn't vaporize, because air's humidity is at 100%, you won't feel any cold.
ahhhhhhhhh !!..Thank Ewe Lightarrow...so the very act of evaporisation takes the heat from me ? does this mean if a drop of water was evaporating from a table then the table beneath the drop of water would be colder than the dry part of the table ?
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Because of water vaporization: the process requires heat, and it takes it from your skin. If water couldn't vaporize, because air's humidity is at 100%, you won't feel any cold.
ahhhhhhhhh !!..Thank Ewe Lightarrow...so the very act of evaporisation takes the heat from me ? does this mean if a drop of water was evaporating from a table then the table beneath the drop of water would be colder than the dry part of the table ?
Got it!
By the way: this is the principle of a snow gun, for example:
http://en.wikipedia.org/wiki/Snow_gun
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Because of water vaporization: the process requires heat, and it takes it from your skin. If water couldn't vaporize, because air's humidity is at 100%, you won't feel any cold.
ahhhhhhhhh !!..Thank Ewe Lightarrow...so the very act of evaporisation takes the heat from me ? does this mean if a drop of water was evaporating from a table then the table beneath the drop of water would be colder than the dry part of the table ?
Got it!
I am a klevur sheepy ! [;)]
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The cooling down process is really quite clever. The speed of the water molecules varies from slow to fast - their Kinetic Energies cover a huge range but the temperature of the water is the Average KE.
The only molecules that will leave the surface will be the ones with higher KE. When they've gone, the average KE will be less - so COOLER!
With a wind blowing over the surface, all the fast molecules are lost so it cools quicker than for no wind, when many of them will drop back in, returning their KE.
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Cool question So its basically like the aerosel spray that is cold on your hand its the quick evaporization thatmakes it cold on your hand.......as some propellents evaporate at slower rates..eh?
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The cooling down process is really quite clever. The speed of the water molecules varies from slow to fast - their Kinetic Energies cover a huge range but the temperature of the water is the Average KE.
The only molecules that will leave the surface will be the ones with higher KE. When they've gone, the average KE will be less - so COOLER!
With a wind blowing over the surface, all the fast molecules are lost so it cools quicker than for no wind, when many of them will drop back in, returning their KE.
Thank ewe Sohiecentaur.
This is great information and I remain ever so grateful to all the klevur peeps who help us here. What a wonderful resource.