Science facts

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blunthead

Well-Known Member
Aug 2, 2006
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Atlanta GA
The reason electric fans work to cool a person is not by cooling air. Heat radiates out of human beings through skin cells. (When a person is hot the process of getting rid of the excess heat is speeded by perspiration which evaporates. When the air is humid as well as hot the extra moisture in the air slows down evaporation. This is why people feel so much hotter in a humid environment at a given temperature than they do in a less humid one at the same temperature.) Fanning pushes the heated air surrounding a person away from the skin so that the person feels, and is, cooler.

So, keeping a fan on in a room which contains nothing which is alive is a waste of energy.
 

fljoe0

Cantre Member
Apr 5, 2008
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The reason electric fans work to cool a person is not by cooling air. Heat radiates out of human beings through skin cells. (When a person is hot the process of getting rid of the excess heat is speeded by perspiration which evaporates. When the air is humid as well as hot the extra moisture in the air slows down evaporation. This is why people feel so much hotter in a humid environment at a given temperature than they do in a less humid one at the same temperature.) Fanning pushes the heated air surrounding a person away from the skin so that the person feels, and is, cooler.

So, keeping a fan on in a room which contains nothing which is alive is a waste of energy.

I saw a TV ad a while back for ceiling fans that claimed the fans cooled the room temperature. I was yelling at the screen, LIAR! ;-D
 

blunthead

Well-Known Member
Aug 2, 2006
80,755
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Atlanta GA
Soap works to clean due to its unique molecular structure. When someone is "dirty" it means that dust and other environmental substances have mixed with oils which stick to the skin. Water alone can't wash it off because oil and water don't mix - the water simply rolls off. The reason oil and water don't mix is because oil molecules are non-polar - they have no electrical charge - while water molecules are polar - one end carries a positive charge, the other a negative one. Water molecules are consequently magnetically attracted to charged molecules, including each other, and not attracted to non-polar molecules.

A soap molecule is engineered with two parts rendering it somewhat a snakelike; the body of the snake is a lengthy non-polar structure, and the head an attached polar structure. The two can exist together because the attachment, a glycerol molecule, has both polar and non-polar properties. The dual electrical nature of the soap molecule - the non-polar body, and the polar head - allow it to mix with both water and oil.

What happens is when soapy water is applied to dirty skin the attraction the water molecules have toward one another force them under and around the oil molecules, surrounding and isolating them into microscopic globules. The oil molecules can mix with the water since it contains soap which has non-polar properties as well as polar, so the oil is lifted away from the skin, and with more water applied washes the dirty solution away.
 
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Walter Oobleck

keeps coming back...or going, and going, and going
Mar 6, 2013
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220px-FibonacciChamomile.PNG


Fibonacci sequences appear in biological settings
This is something that has always amazed me.
 

Neesy

#1 fan (Annie Wilkes cousin) 1st cousin Mom's side
May 24, 2012
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Winnipeg, Manitoba, Canada
Soap works to clean due to its unique molecular structure. When someone is "dirty" it means that dust and other environmental substances have mixed with oils which stick to the skin. Water alone can't wash it off because oil and water don't mix - the water simply rolls off. The reason oil and water don't mix is because oil molecules are non-polar - they have no electrical charge - while water molecules are polar - one end carries a positive charge, the other a negative one. Water molecules are consequently magnetically attracted to charged molecules, including each other, and not attracted to non-polar molecules.

A soap molecule is engineered with two parts rendering it somewhat a snakelike; the body of the snake is a lengthy non-polar structure, and the head an attached polar structure. The two can exist together because the attachment, a glycerol molecule, has both polar and non-polar properties. The dual electrical nature of the soap molecule - the non-polar body, and the polar head - allow it to mix with both water and oil.

What happens is when soapy water is applied to dirty skin the attraction the water molecules have toward one another force them under and around the oil molecules, surrounding and isolating them into microscopic globules. The oil molecules can mix with the water since it contains soap which has non-polar properties as well as polar, so the oil is lifted away from the skin, and with more water applied washes the dirty solution away.
So if I put about a cup of Epsom salts and some bubble bath in my tub and soak for at least five minutes (in hot water) I am not going to get clean? I use soap on my underarms, feet, etc. and use shampoo on my hair but I do not soap my entire body. Now you have me wondering just how clean I am! :m_cat: :bath:
p.s. I have a very deep tub too!
 

blunthead

Well-Known Member
Aug 2, 2006
80,755
195,461
Atlanta GA
So if I put about a cup of Epsom salts and some bubble bath in my tub and soak for at least five minutes (in hot water) I am not going to get clean? I use soap on my underarms, feet, etc. and use shampoo on my hair but I do not soap my entire body. Now you have me wondering just how clean I am! :m_cat: :bath:
p.s. I have a very deep tub too!
I'm reading up on your question, Neese. I suggest you read what I'm reading as well, in order for you to best get your answer...
Bubble bath - Wikipedia, the free encyclopedia

Bathing - Wikipedia, the free encyclopedia

Bath salts - Wikipedia, the free encyclopedia
 

blunthead

Well-Known Member
Aug 2, 2006
80,755
195,461
Atlanta GA
Almost every substance on Earth shrinks to its ultimate point of smallness when in low enough temperatures. They do this because coldness decreases the vibration of substances' particles. Consequently, liquids eventually become solids because as particles' vibration diminishes they get closer to one another. Water is an exception in that a volume of liquid water shrinks to a certain temperature, then just before becoming solid expands slightly. The reason for this phenomenon has to do with "hydrogen bonding"...

Polar molecules, such as water molecules, have a weak, partial negative charge at one region of the molecule (the oxygen atom in water) and a partial positive charge elsewhere (the hydrogen atoms in water).

Hbonds_water.gif
Thus when water molecules are close together, their positive and negative regions are attracted to the oppositely-charged regions of nearby molecules. The force of attraction, shown here as a dotted line, is called a hydrogen bond. Each water molecule is hydrogen bonded to four others.

The hydrogen bonds that form between water molecules account for some of the essential — and unique — properties of water.

...so, hydrogen bonds force water molecules slightly apart in a state of dynamic tension.
 

Walter Oobleck

keeps coming back...or going, and going, and going
Mar 6, 2013
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isn't there something in our universe that is unexplainable? I'm remembering something posted here years back...as I recall it had to do with...maybe something to do with the 'start' of the universe, big bang type stuff...as in particles or substances some place in the universe they haven't figured out as yet...maybe they don't "do" anything...don't recall exactly sorry.

and then there's that phenomenon whereby some things react differently when observed. dunno what the official word for that is, but it is a curiosity