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Author Topic: Why Do I Feel Cold When Wet ?  (Read 9996 times)

Offline neilep

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Why Do I Feel Cold When Wet ?
« on: 10/08/2009 14:15:04 »
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 !


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
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Offline lightarrow

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Why Do I Feel Cold When Wet ?
« Reply #1 on: 10/08/2009 14:23:01 »
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.
 

Offline neilep

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Why Do I Feel Cold When Wet ?
« Reply #2 on: 10/08/2009 14:26:09 »
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 ?

 

Offline lightarrow

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Why Do I Feel Cold When Wet ?
« Reply #3 on: 10/08/2009 14:28:18 »
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
« Last Edit: 10/08/2009 14:32:16 by lightarrow »
 

Offline neilep

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Why Do I Feel Cold When Wet ?
« Reply #4 on: 10/08/2009 14:29:50 »
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 !  ;)
 

lyner

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Why Do I Feel Cold When Wet ?
« Reply #5 on: 10/08/2009 14:34:06 »
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.
 

Offline Karen W.

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Why Do I Feel Cold When Wet ?
« Reply #6 on: 11/08/2009 04:26:22 »
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?
 

Offline neilep

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Why Do I Feel Cold When Wet ?
« Reply #7 on: 11/08/2009 12:36:32 »
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.
 

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Why Do I Feel Cold When Wet ?
« Reply #7 on: 11/08/2009 12:36:32 »

 

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