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Author Topic: Why Do Clothes Dry Quicker Outside ?  (Read 11108 times)

Offline neilep

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Why Do Clothes Dry Quicker Outside ?
« on: 02/07/2009 20:06:24 »
Dearest Peeps Who Know So Much !

As a sheepy I of course hang clothes up on the washing line. I mean ..it's obvious isn't it ?..Woolly sheepy thing = clothes Hanger-Upper...........obvious.. !!..blatant even..

Here look at this fine example of my hanging washing up:


FROM THE SIDE:...KWALITY !




VOILA...and now from the top !!




Now THAT is kwality hangage and ewe know it !! Notice how I have klevurly opened up my shorts and top to allow air inside ? I thought of that all by myself ! *le smug*

Now then, I understand that my clothes will dry quicker outside rather than inside ?..why's that then ?..Why do my clothes dry quicker outside rather than inside ?....I can understand if it was like...windy...but on a very calm still day...the clothes still dry quicker outside !..and I don't know why.

As a firm believer in empirical study I snuck into my neighbours house at 3am and hosed down all his clothes whilst they were hanging in his wardrobe. After this, I then went and hanged a wet tissue on my hanging line and it's true...my tissue dried a lot quicker !!

So, what's it all about ?


Hugs and shmishes


mwah mwah mwah


Neil
I Wear Soaking Stockings
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Offline wolfekeeper

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Why Do Clothes Dry Quicker Outside ?
« Reply #1 on: 02/07/2009 22:34:54 »
Damp air, like in a cupboard or in the middle of your trousers doesn't absorb moisture so well. In the open air the moist air will be slightly heavier and will tend to fall away from the clothes; the lack of restrictions will help the flow move and you'll get more flow and it will dry quicker.

Also, outside, particularly if the sun is up, it's often warmer, warm air can absorb more water than cold air (that's how demisters on cars work of course).
 

Offline Chemistry4me

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Why Do Clothes Dry Quicker Outside ?
« Reply #2 on: 03/07/2009 05:43:23 »
Outside there is often a breeze so more 'new' air can pass over the clothes, this means more water is absorbed.
 

Offline rosalind dna

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Why Do Clothes Dry Quicker Outside ?
« Reply #3 on: 03/07/2009 16:02:24 »
Unless it rains, Neil then your clothes get an extra rinse LOL LOL
 

lyner

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Why Do Clothes Dry Quicker Outside ?
« Reply #4 on: 03/07/2009 17:19:29 »
I hate to rain on anyone's parade but the model involving "air absorbing water" is flawed. It only "behaves as if".
What governs the rate at which the clothes dry is the vapour pressure of the water at the ambient temperature and the partial pressure of the water on the atmosphere. When the air is 'saturated' the partial pressure is the same as the vapour pressure.
If you hung clothes in an air free space with just the same density of water vapour in it and at the same temperature, they would dry at the same rate as in air.

Strange that it is so seldom described that way!!?

The air does get involved when there is some wind, though, I think. A current of air molecules brushing against the cloth may remove water molecules from near the surface faster than without the presence of air. Hand dryers with strong blowers work best.
 

Offline Chemistry4me

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Why Do Clothes Dry Quicker Outside ?
« Reply #5 on: 03/07/2009 23:42:39 »
Ah, Mr sophiecentaur, you always make the most eloquent posts that never ceases to astonish me, you even threw in a dry pun for humour! :)
 

lyner

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Why Do Clothes Dry Quicker Outside ?
« Reply #6 on: 04/07/2009 01:36:35 »
Too kind. Too kind, dear boy.
 

Offline wolfekeeper

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Why Do Clothes Dry Quicker Outside ?
« Reply #7 on: 04/07/2009 19:41:21 »
What governs the rate at which the clothes dry is the vapour pressure of the water at the ambient temperature and the partial pressure of the water on the atmosphere.
Yes, diffusion, but I think there may also be convection though; the wetter air is going to be heavier and will tend to sink. When you get airflow happening then it matters what there is around; if you're in a cupboard the flow will be a lot slower than if you're hanging it on a line outside in free space.

That also relates to the inside of trousers on the line as well; the airflow through the trousers will be quite a bit slower and hence dry less quickly.
 

Offline Bored chemist

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Why Do Clothes Dry Quicker Outside ?
« Reply #8 on: 04/07/2009 20:03:57 »
"the wetter air is going to be heavier and will tend to sink. "
Why?
 

Offline wolfekeeper

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Why Do Clothes Dry Quicker Outside ?
« Reply #9 on: 04/07/2009 20:11:41 »
Actually my bad, it gets lighter and will tend to rise:

http://en.wikipedia.org/wiki/Density_of_air#Water_vapor
 

lyner

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Why Do Clothes Dry Quicker Outside ?
« Reply #10 on: 05/07/2009 00:24:25 »
"the wetter air is going to be heavier and will tend to sink. "
Why?
That's another popular misapprehension. After all: "it stands to reason dunnit?" A wet sponge is heavier than a dry one - so the logical conclusion is . ... . .
 

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Why Do Clothes Dry Quicker Outside ?
« Reply #10 on: 05/07/2009 00:24:25 »

 

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