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We recently had an Team EEP Superbowl GTG at RoxyB5 Manor in beautiful CT this past weekend. While we were waiting for the game to begin, and while we were axiously waiting for Chef JonBoy's world famous "Drunken Chicken" to feat on, PJ (aka Barrelman17) posed an interesting & mind-bending physics challenge. I thought this would be impossible... but wanted to pose the question to all you smarties out there...

Here it goes....

If you took a bucket of water (assume 3 gallons, room temp) & threw it the contents up in the air, how cold would it have to be for the water to freeze before it hit the ground. My answer was, "pretty damned cold"... but then thought it was impossible...

Your thoughts?
 

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isn't it somewhere past -20 degrees?

i remember reading about how gold miners used to know how cold it was in the yukon by spitting. if your spit froze and crackled before it hit the ground, then they knew it was below X degrees.

but then, spit would be close to body temp, and it's also a much smaller quantity than 3 gallons of water, so i dunno.
 

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I saw a field reporter on the news a week or two ago when temps were below zero...don't remember where or exact temps...

He threw a cup of hot water in the air and it turned to ice crystals before it hit the ground. For a bucket to freeze, the required temp vary, depending on how high the water would be thrown, and thus how much it could dissipate its heat into the air.
 

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redb5sdca said:
I would think if it was cold enough to freeze in the air before hitting the ground you would have to defrost in order to even get it out of the bucket :???:
No, no, no. The water's room temperature. You take the bucket directly outside from your house, not a bucket of water that you've left outside to freeze. :)
 

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I tried washing my car in 8 degree (-8 with windchill) weather. The water came out of the hose, hit my car and and was frozen within 5 minutes. I also had a bucket which I had put some water into at the same time. When I was done icing the car over (15 minutes), it was frozen...

doesn't answer the question, but it could freeze...very fast.
 

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Altair 4 said:
redb5sdca said:
I would think if it was cold enough to freeze in the air before hitting the ground you would have to defrost in order to even get it out of the bucket :???:
No, no, no. The water's room temperature. You take the bucket directly outside from your house, not a bucket of water that you've left outside to freeze. :)

either way I think if it was cold enough to freeze three gallons before hitting the ground? think about it almost soon as it hits that much cold outthere the whole bucket would be frozen. Also I beleive boeser said it best the proper temperaure for this project is too damn cold :shock:

(p.s did you know there is no such thing as cold air? technically it is air minus heat) found that out this year at my new air conditioning job.
 

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-82 F for exactly 3 gallons thrown into the air for 1.65 seconds with a relative humidity of 15% and a light wind from the southeast :wink: BTW - This should probably be done at night to reduce any potential effects of radiant heat :p

Carl III
 

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It would really depend upon the droplet size as well as temperature. Water cools via surface area. The larger the droplet the less surface area (by volume).. the slower the cooling. That's why the bucket of water would remain liquid before the water went into the air but the drops would freeze. Too many factors for me to calculate this but I read that on mt. Washigton, the author of this article got a thrown bucket of water to do that at -38.
 

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redb5sdca said:
...either way I think if it was cold enough to freeze three gallons before hitting the ground? think about it almost soon as it hits that much cold outthere the whole bucket would be frozen.
No - it takes time for 3 gallons of water to cool to freezing. When you put stuff in the freezer, does it freeze instantly? No. Some engineer here can give you the technical explanation. We aren't talking about dipping stuff in liquid nitrogen or something like that.

Oh, wait, you're in San Diego! Well, it would only seem like it would freeze instantly to you! :)
 

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Altair 4 said:
redb5sdca said:
...either way I think if it was cold enough to freeze three gallons before hitting the ground? think about it almost soon as it hits that much cold outthere the whole bucket would be frozen.
No - it takes time for 3 gallons of water to cool to freezing. When you put stuff in the freezer, does it freeze instantly? No. Some engineer here can give you the technical explanation. We aren't talking about dipping stuff in liquid nitrogen or something like that.

Oh, wait, you're in San Diego! Well, it would only seem like it would freeze instantly to you! :)
:weirdo: :weirdo:
 

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well lets see... given some knowledge of science...

for starters, the bucket wouldnt freeze as soon as you came out. The water density in the bucket greats small amounts of heat, thus the bucket as a whole, unmoved, will take longer to freeze. (atom molcules rubbing, bumbing, and slaming into eachother cause the heat in dense consentrations of liquid)

Now, throwing the water up into the air, you have taken that large 3 gallon density and spread it out. Assuming you throw out like to throw the water onto a fire or out onto plants or something, the water fans out very thin.

What you would need to do is figure out the room temp of the water, how much, and the density of the water in the air. Once you have that, then figure out how long and how cold it would have to be to freeze what normally (aka low or simular density as it is in the air) in a very short amount of time. Take that and times it by you throw in the air and you should have it.

Any scientists around.... :D
 

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Good answer Joe...

What you'll find is that it's not how fast the water freezes, it's how fast it evaporates. When it's that cold (minus whatever) the air is very dry, and the dewpoint of the air is also very low. Because of this, most of the water doesn't freeze, but evaporates. You 3 gallons would turn into an ass load of steam.

Now if you boiled it, it would be alot easier. I did this with 3 quarts of water (boiled in microwave) the other night to show my 11 yo. It was about -10F... not a single drop of water hit the snow. It all evaporated, and froze (so I guess it did hit the snow, but it wasn't water any more.)

Try it with a cup of water (nuked) when it's near zero... looks cool, and makes a cool noise as the water rapidly (very) evaporates.

As far as the spit... -42F, and a nice arc on the lugie will get you 'a frozen lugie treat B4 it hits the ground (personal experience) :thumbup:
 
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