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"Out of fuel, out of hope: 'Help, I'm in the water'"



 
 
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  #141  
Old May 1st 05, 03:42 AM
Morgans
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"Steven P. McNicoll" wrote in message
news

"Morgans" wrote in message
...

It is arguing nits, but I'll play the game you started.

If the water of the lake was all indeed at 32 degrees, it would all be a
giant ice cube. If it were all at 32.1 degrees, it would all be liquid.
The wave action has nothing to do with it.


So in other words, the physical state of water is a function of

temperature
alone?


Zactly. Waves stir the water, and bring up the warmer water to the surface,
if there is warm enough water down there to keep it from freezing. There is
ultimate proof that waves are not enough, because some winters, the Great
Lakes still freeze over. I'll bet there were waves, when it started to
freeze. The air was cold enough to get the surface temperature down to
32.0, or lower. Period.

Same principle with some boats at marinas that stay in the water all winter.
They put an air bubble pump with the hose under the boat, to keep the water
circulating. It works pretty well.
--
Jim in NC

  #142  
Old May 1st 05, 03:56 AM
Morgans
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"Jeff Shirton" wrote

Sorry, but wrong.

You seem to be basing your argument on "the freezing point of water is

32",
and assuming that this means that any H2O at 32 will be solid "frozen".

However, it is equally true that "the melting point of water is 32", which
means that when solid water gets to 32 degrees, it melts (at that temp.)
and becomes water (at that temp.)


True. It actually needs to get sligtly below 32.0 to freeze.


But wait... This means that I'm trying to say that water can be both
solid *and* liquid at 32 F? Yes, definitely. It's a trick chemists use
all the time, as a mixture of ice and water will maintain a constant
temp. (of 32, both the ice and the water) until all of the ice melts.

You have a body of water at 32.0 F. If you remove sufficient heat,
it cools to ICE at 32.0 F. The heat lost to change a substance
from liquid at the freezing point to solid AT THE SAME TEMP
is called the "latent heat of fusion". But the point is that during
the change of state, the temperature does not change. The temperature
remains the same.

That is to say, once water reaches the freezing point, it doesn't
"instantly" change to ice. More heat is needed to be released
until it to solidify, and the latent heat of fusion is *much* more
than the heat needed to be lost to reduce temp.


True, but that has nothing to do with the water temperature. It takes
longer, but that was not part of the arguement. We were dealing with temp
only, not how long it takes, or how much energy has to change hands.

Actually, wave action is kinetic energy. And so a body of
water with wave action will contain more energy than a
stagnant body of water, and so more energy will be needed
to be lost for it to freeze.


The amount of kinetic energy in the waves, again is not the issue. Not
time, only temperature. When it goes below freezing, it freezes. I don't
give a rat's a** how much energy has to change hands to get to the
temperature. All we were talking about was the final result; measure the
temperature. The end observation is all we were talking about.

Besides, the amount of kinetic energy in waves compared to the energy
exchange to freeze water is negligible. It could be argued that the waves
actually help the water to cool more rapidly, due to the spray evaporating,
and cooling the water by changing states from liquid to vapor.
--
Jim in NC

  #143  
Old May 1st 05, 04:49 AM
Jeff Shirton
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"Morgans" wrote in message
...

You seem to be basing your argument on "the freezing point of water is
32", and assuming that this means that any H2O at 32 will be solid
"frozen".

However, it is equally true that "the melting point of water is 32",
which
means that when solid water gets to 32 degrees, it melts (at that temp.)
and becomes water (at that temp.)


True. It actually needs to get sligtly below 32.0 to freeze.


Sorry, but wrong again.

It will completely freeze *before* going below 32 degrees.

Where do you get your "information" from, anyway?

That is to say, once water reaches the freezing point, it doesn't
"instantly" change to ice. More heat is needed to be released
until it to solidify, and the latent heat of fusion is *much* more
than the heat needed to be lost to reduce temp.


True, but that has nothing to do with the water temperature.


Certainly it does.

Change of state doesn't happen until the water is reduced
to 32 degrees.

And then lowering of ice temperature below 32 degrees
doesn't happen until all the surrrounding water (in contact
with the ice) has solidified.

The amount of kinetic energy in the waves, again is not the issue. Not
time, only temperature. When it goes below freezing, it freezes.


Wrong again.

When it goes below freezing, it is already *frozen*.

I don't give a rat's a** how much energy has to change
hands to get to the temperature.


When one must resort to vulgar language, it is an admission
that you have already lost the argument. You have already
demonstrated your lack of knowledge in this area, I'm afraid
at this point you will need to support your novel ideas with
actual evidence before they will be believed.

Besides, the amount of kinetic energy in waves compared
to the energy exchange to freeze water is negligible.


And the latent energy of fusion needed to transform the
liquid water to solid ice is anything *but* "negligible",
and no temperature change happens until the change of
state is complete. That's what you don't seem to understand.

At the melting/freezing point, the energy change ceases to
change the temperature, and *instead* goes towards changing
the state of the water.

And as others have noted, the fact that the lake isn't pure
water throws the "32 degrees" number right out the window.
I don't know where you're getting this "32.1 degrees" or
"slightly below 32 degrees" numbers, but you seem to be
making them up out of thin air.

You might want to review some high school or college
physics textbooks, or else review the following:

http://www.google.ca/search?num=100&...#267,17,Water: Warming Curveetc. Jim in NC--Jeff Shirton jshirton at cogeco dotca Keep thy airspeed up, lest the earth come from below and smite thee. — William KershnerChallenge me (Theophilus) for a game of chess at Chessworld.net!

  #144  
Old May 1st 05, 12:41 PM
Happy Dog
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"Morgans" wrote in
"Jeff Shirton" wrote

Sorry, but wrong.

You seem to be basing your argument on "the freezing point of water is

32",
and assuming that this means that any H2O at 32 will be solid "frozen".

However, it is equally true that "the melting point of water is 32",
which
means that when solid water gets to 32 degrees, it melts (at that temp.)
and becomes water (at that temp.)


True. It actually needs to get sligtly below 32.0 to freeze.

But wait... This means that I'm trying to say that water can be both
solid *and* liquid at 32 F? Yes, definitely. It's a trick chemists use
all the time, as a mixture of ice and water will maintain a constant
temp. (of 32, both the ice and the water) until all of the ice melts.

You have a body of water at 32.0 F. If you remove sufficient heat,
it cools to ICE at 32.0 F. The heat lost to change a substance
from liquid at the freezing point to solid AT THE SAME TEMP
is called the "latent heat of fusion". But the point is that during
the change of state, the temperature does not change. The temperature
remains the same.

That is to say, once water reaches the freezing point, it doesn't
"instantly" change to ice. More heat is needed to be released
until it to solidify, and the latent heat of fusion is *much* more
than the heat needed to be lost to reduce temp.


True, but that has nothing to do with the water temperature. It takes
longer, but that was not part of the arguement. We were dealing with temp
only, not how long it takes, or how much energy has to change hands.

Actually, wave action is kinetic energy. And so a body of
water with wave action will contain more energy than a
stagnant body of water, and so more energy will be needed
to be lost for it to freeze.


The amount of kinetic energy in the waves, again is not the issue. Not
time, only temperature. When it goes below freezing, it freezes. I don't
give a rat's a** how much energy has to change hands to get to the
temperature. All we were talking about was the final result; measure the
temperature. The end observation is all we were talking about.

Besides, the amount of kinetic energy in waves compared to the energy
exchange to freeze water is negligible. It could be argued that the waves
actually help the water to cool more rapidly, due to the spray
evaporating,
and cooling the water by changing states from liquid to vapor.
--

Eloquently written. And wrong. Latent heat is your considerate friend.

Revelation through xposting...

moo


  #145  
Old May 1st 05, 01:44 PM
Steven P. McNicoll
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"Morgans" wrote in message
...

So in other words, the physical state of water is a function of
temperature
alone?


Zactly.


Then how do you explain the triple point?


  #146  
Old May 3rd 05, 11:21 PM
Bill G
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On 28 Apr 2005 13:06:14 -0700, "Peter R."
wrote:

Mortimer wrote:

His biggest risk was hypothermia. If he'd only had a light....


A light? As long as we are wishing here, if only he wore a wetsuit and
life preserver equipped with a McMurdo FastFind Plus PLB and a flashing
beacon.



And maybe an inflatable raft on board !

Bill

 




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