Don't believe it
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I saw a clip on the news last night where in the US, to demonstrate it's getting pretty chilly, they threw some boiling water in the air only to have it fall to earth as snow. Like a scene out of the dismal 'Day after tomorrow'. Really? So it's going to drop 100c in a second and also dissipate it's latent heat to solidify in the space of a second flat in air - a very good heat insulator? I'm having a very hard time accepting this. What says the CodeProject community?
Regards, Rob Philpott.
It doesn't even need to be freezing to use a Snow Cannon[^]
Wrong is evil and must be defeated. - Jeff Ello[^]
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The convection currents in the warm water help in the rapid heat exchange which is why warm water is used. (I don't have a citation other than a colleague who showed me the explanation online yesterday)
“That which can be asserted without evidence, can be dismissed without evidence.”
― Christopher Hitchens
Ah! An interesting new angle...
Regards, Rob Philpott.
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I saw a clip on the news last night where in the US, to demonstrate it's getting pretty chilly, they threw some boiling water in the air only to have it fall to earth as snow. Like a scene out of the dismal 'Day after tomorrow'. Really? So it's going to drop 100c in a second and also dissipate it's latent heat to solidify in the space of a second flat in air - a very good heat insulator? I'm having a very hard time accepting this. What says the CodeProject community?
Regards, Rob Philpott.
Mpemba effect[^] /Fredrik
My Android apps in Google Play; Oakmead Apps
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I saw a clip on the news last night where in the US, to demonstrate it's getting pretty chilly, they threw some boiling water in the air only to have it fall to earth as snow. Like a scene out of the dismal 'Day after tomorrow'. Really? So it's going to drop 100c in a second and also dissipate it's latent heat to solidify in the space of a second flat in air - a very good heat insulator? I'm having a very hard time accepting this. What says the CodeProject community?
Regards, Rob Philpott.
it is actually so that hot water freezes more quickly than cold water, although it is not yet known why.
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The convection currents in the warm water help in the rapid heat exchange which is why warm water is used. (I don't have a citation other than a colleague who showed me the explanation online yesterday)
“That which can be asserted without evidence, can be dismissed without evidence.”
― Christopher Hitchens
Not quite - boiled water has dissolved gasses removed, and will freeze faster. When you heat water on a stove to boiling point, you will see bubbles form for some time before the water reaches the boiling point. This is dissolved gases coming out of solution, and if you capture the bubbles, you will see that their content is not H2O. Once the water reaches boiling point ("rolling boil"), then the water is changing phase and the content of gas emitted is water vapor (H2O). Water (even boiling water) that has the dissolved gases removed will freeze faster than warm or even cold water.
Never moon a werewolf. - Harvey
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it is actually so that hot water freezes more quickly than cold water, although it is not yet known why.
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I saw a clip on the news last night where in the US, to demonstrate it's getting pretty chilly, they threw some boiling water in the air only to have it fall to earth as snow. Like a scene out of the dismal 'Day after tomorrow'. Really? So it's going to drop 100c in a second and also dissipate it's latent heat to solidify in the space of a second flat in air - a very good heat insulator? I'm having a very hard time accepting this. What says the CodeProject community?
Regards, Rob Philpott.
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I saw a clip on the news last night where in the US, to demonstrate it's getting pretty chilly, they threw some boiling water in the air only to have it fall to earth as snow. Like a scene out of the dismal 'Day after tomorrow'. Really? So it's going to drop 100c in a second and also dissipate it's latent heat to solidify in the space of a second flat in air - a very good heat insulator? I'm having a very hard time accepting this. What says the CodeProject community?
Regards, Rob Philpott.
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I saw a clip on the news last night where in the US, to demonstrate it's getting pretty chilly, they threw some boiling water in the air only to have it fall to earth as snow. Like a scene out of the dismal 'Day after tomorrow'. Really? So it's going to drop 100c in a second and also dissipate it's latent heat to solidify in the space of a second flat in air - a very good heat insulator? I'm having a very hard time accepting this. What says the CodeProject community?
Regards, Rob Philpott.
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I saw a clip on the news last night where in the US, to demonstrate it's getting pretty chilly, they threw some boiling water in the air only to have it fall to earth as snow. Like a scene out of the dismal 'Day after tomorrow'. Really? So it's going to drop 100c in a second and also dissipate it's latent heat to solidify in the space of a second flat in air - a very good heat insulator? I'm having a very hard time accepting this. What says the CodeProject community?
Regards, Rob Philpott.
yes, it's real. and my FB feed is currently full of people demonstrating that it works in their back yards. cold air, pot full of hot water => snow
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Not quite - boiled water has dissolved gasses removed, and will freeze faster. When you heat water on a stove to boiling point, you will see bubbles form for some time before the water reaches the boiling point. This is dissolved gases coming out of solution, and if you capture the bubbles, you will see that their content is not H2O. Once the water reaches boiling point ("rolling boil"), then the water is changing phase and the content of gas emitted is water vapor (H2O). Water (even boiling water) that has the dissolved gases removed will freeze faster than warm or even cold water.
Never moon a werewolf. - Harvey
Thanks - (in danger of being a complete pain in the arse) has this theory been peer reviewed scientifically? I ask this as having just done a quickish google there do appear to be a few theories none of which have been conclusively proven correct. e.g. Mpemba theory[^]
“That which can be asserted without evidence, can be dismissed without evidence.”
― Christopher Hitchens
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I saw a clip on the news last night where in the US, to demonstrate it's getting pretty chilly, they threw some boiling water in the air only to have it fall to earth as snow. Like a scene out of the dismal 'Day after tomorrow'. Really? So it's going to drop 100c in a second and also dissipate it's latent heat to solidify in the space of a second flat in air - a very good heat insulator? I'm having a very hard time accepting this. What says the CodeProject community?
Regards, Rob Philpott.
More to the point: given the amount of snow they already have, why are they adding any blooming more? :laugh:
Never underestimate the power of stupid things in large numbers --- Serious Sam
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Thanks - (in danger of being a complete pain in the arse) has this theory been peer reviewed scientifically? I ask this as having just done a quickish google there do appear to be a few theories none of which have been conclusively proven correct. e.g. Mpemba theory[^]
“That which can be asserted without evidence, can be dismissed without evidence.”
― Christopher Hitchens
When taking engineering courses it was explained by the fact the hot water is losing energy already where as cold water has to start losing heat(energy). Poor man's explanation after 30 plus years of forgetting. At the time we calculated the "proof".
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Yah believe it. We have had frost quakes[^] in Canada here.
Silvabolt wrote:
frost quakes
I read that Frosted Flakes[^] :-O
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More to the point: given the amount of snow they already have, why are they adding any blooming more? :laugh:
Never underestimate the power of stupid things in large numbers --- Serious Sam
:thumbsup:
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When taking engineering courses it was explained by the fact the hot water is losing energy already where as cold water has to start losing heat(energy). Poor man's explanation after 30 plus years of forgetting. At the time we calculated the "proof".
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That is saying that energy loss has momentum. I don't think that is true, and it should be relatively easy to prove in a lab. [Haven't done it myself...]
Never moon a werewolf. - Harvey
As I say I do not remember exactly what the science was but I remember doing the calculations.
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I saw a clip on the news last night where in the US, to demonstrate it's getting pretty chilly, they threw some boiling water in the air only to have it fall to earth as snow. Like a scene out of the dismal 'Day after tomorrow'. Really? So it's going to drop 100c in a second and also dissipate it's latent heat to solidify in the space of a second flat in air - a very good heat insulator? I'm having a very hard time accepting this. What says the CodeProject community?
Regards, Rob Philpott.
Don't forget we use Fahrenheit so -15 here is a lot colder than -15 there : )
Need custom software developed? I do custom programming based primarily on MS tools with an emphasis on C# development and consulting. "And they, since they Were not the one dead, turned to their affairs" -- Robert Frost "All users always want Excel" --Ennis Lynch
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I saw a clip on the news last night where in the US, to demonstrate it's getting pretty chilly, they threw some boiling water in the air only to have it fall to earth as snow. Like a scene out of the dismal 'Day after tomorrow'. Really? So it's going to drop 100c in a second and also dissipate it's latent heat to solidify in the space of a second flat in air - a very good heat insulator? I'm having a very hard time accepting this. What says the CodeProject community?
Regards, Rob Philpott.
It works - really! A couple of points, though... The liquid immediately separates into droplets, vastly increasing the surface area exposed to the cold, plus it is moving, effectively the same as a stiff breeze. Both factors contribute to the rapid freezing. Besides, it's been really, really cold. It was so cold, in fact, that Miley Cyrus stuck to her wrecking ball, and a Liberal in D.C. was spotted with his hands in his own pockets!
Will Rogers never met me.
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It works - really! A couple of points, though... The liquid immediately separates into droplets, vastly increasing the surface area exposed to the cold, plus it is moving, effectively the same as a stiff breeze. Both factors contribute to the rapid freezing. Besides, it's been really, really cold. It was so cold, in fact, that Miley Cyrus stuck to her wrecking ball, and a Liberal in D.C. was spotted with his hands in his own pockets!
Will Rogers never met me.
Roger Wright wrote:
and a Liberal in D.C. was spotted with his hands in his own pockets!
:thumbsup::thumbsup:
