Reason of hot water 'float' on the cold water

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Discussion Overview

The discussion revolves around the phenomenon of hot water floating on cold water, exploring potential explanations and models. Participants examine the underlying principles of density, energy, and molecular interactions, while also considering the implications of their models in relation to observed behaviors of water at different temperatures.

Discussion Character

  • Exploratory
  • Technical explanation
  • Debate/contested

Main Points Raised

  • One participant suggests that hot water floats on cold water due to higher energy particles being more powerful, rather than differences in density.
  • Another participant challenges this view by questioning why water at 0°C floats on water at 4°C, suggesting that the model does not account for the behavior of water as it approaches freezing.
  • A different participant notes that the model appears to simulate a gas rather than liquid water, pointing out the absence of surface tension and molecular bonding effects in the simulation.
  • Another participant comments on the lack of interaction terms in the model, indicating that it may not accurately represent the behavior of water due to missing factors like hydrogen bonding.
  • One participant acknowledges the gas-like behavior of the model and expresses a desire to create a more accurate representation of heating and convection currents.

Areas of Agreement / Disagreement

Participants express differing views on the reasons behind the behavior of hot and cold water, with no consensus reached. There are competing explanations regarding the role of density, energy, and molecular interactions.

Contextual Notes

The discussion highlights limitations in the proposed model, including missing assumptions about molecular interactions and the nature of water at different temperatures. The exploration of surface tension and bonding effects remains unresolved.

ArielGenesis
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i think that the reason of hot water 'float' on the cold water is not because of diffrent density. i make a model of a container containing a higher energy particle (hot water) and lower energy particle (cold water) using action script in flash and uploaded it in geocities. www.geocities.com/arian_m3/heat.swf

from that, it shows that the hot water is MORE (not placed) at the top because it got the power to. while the cold water STAYS (not sink) at the bottom. And thus RESULTING (not beacuse of) a diffrent density. this might not be a perfect model of hot and cold water, but i couldn't find any better yet. the main concept of the script is to move the particle randomly and pulled it downward with gravity.

here is the code if anyone getting interested.

for the hotter particle:
onClipEvent (load) {
_x = 150;
_y = 300;
var vx = random(30)-random(30);
var vy = random(30)-random(30);
var i = 60;
if (_name == "red") {
while (i<>90) {
duplicateMovieClip(_root.red, "red"+i, i);
_parent["red"+i]._x = _x+random(50)-random(50);
_parent["red"+i]._y = _y+random(50)-random(50);
i++;
}
}
}
onClipEvent (enterFrame) {
vx += random(8)-random(8);
vy += random(8)-random(8)+1;
if (_x+vx<=10 or _x+vx>=400) {
vx *= -0.5;
}
if ( _y+vy>=590) {
vy *= -0.5;
}
_x += vx;
_y += vy;
}

and this one is for the colder particle
onClipEvent (load) {
_x = 200;
_y = 300;
var vx = random(10)-random(10);
var vy = random(10)-random(10);
var i = 0;
if (_name == "blue") {
while (i<>50) {
duplicateMovieClip(_root.blue, "blue"+i, i);
_parent["blue"+i]._x = _x+random(50)-random(50);
_parent["blue"+i]._y = _y+random(50)-random(50);
i++;
}
}
}
onClipEvent (enterFrame) {
vx += random(5)-random(5);
vy += random(5)-random(5)+1;
if (_x+vx<=10 or _x+vx>=400) {
vx *= -0.5;
}
if ( _y+vy>=590) {
vy *= -0.5;
}
_x += vx;
_y += vy;
}

feel free to fix my error.
 
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ArielGenesis said:
feel free to fix my error.

Then explain why water at 0C "floats" on top of water at 4C. According to your "model", water at 4C should have "more power" and should be on top of water at 0C. This is certainly not the case since water at 1C or 0C that eventually solidify into ice is on top.

Zz.
 
Neat flik! Looks like a gas though, and I don't see anything in your program regarding surface tension. The flash you have seems to simulate a gas in a gravitational field fairly well. Add the surface tension affects and bonding affects between molecules, then some pressure above the surface, and you may see some differences in the model.
 
Since the code is not self-explanatory, it seems that (from the brief intro in the OP) your hamiltonian contains a kinetic term and a potential term (gravitational) but no interaction terms arising from hydrogen bonding.
 
Q_Goest said:
Neat flik! Looks like a gas though, and I don't see anything in your program regarding surface tension. The flash you have seems to simulate a gas in a gravitational field fairly well. Add the surface tension affects and bonding affects between molecules, then some pressure above the surface, and you may see some differences in the model.
My first reaction too...water isn't a gas. Cool animation though.
 
okay, i think it is my fault, it is gas then, my friend also told me that.

so... what I'm thinking is that if i could make a model of heatting (i failed to make it), following the logic, there could be no convection current
 

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