Reason of hot water 'float' on the cold water

In summary, the conversation discusses a model created using action script in flash to demonstrate why hot water floats on cold water, contrary to the expected result based on density. The code for the model is provided, and suggestions are made to incorporate surface tension and bonding effects to improve the accuracy of the model. It is also mentioned that the model may not accurately represent the behavior of heated water due to the absence of convection currents.
  • #1
ArielGenesis
239
0
i think that the reason of hot water 'float' on the cold water is not becuase 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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  • #2
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.
 
  • #3
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.
 
  • #4
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.
 
  • #5
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.
 
  • #6
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
 

1. Why does hot water float on cold water?

Hot water is less dense than cold water, meaning that it has less mass per unit of volume. When hot water is added to cold water, it creates a density difference, causing the hot water to float on top of the cold water.

2. Is there a scientific explanation for this phenomenon?

Yes, the principle behind hot water floating on cold water is known as the density-temperature relationship. As the temperature of a substance increases, its density decreases, and vice versa.

3. Does this principle apply to all substances?

No, not all substances follow this principle. It mainly applies to liquids, as the density-temperature relationship is affected by the molecular structure and intermolecular forces present in a substance.

4. Can the density-temperature relationship be observed in other situations besides hot water and cold water?

Yes, this principle can be observed in various natural phenomena, such as the formation of ocean currents and the movement of air in the atmosphere. It also has practical applications in industries such as weather forecasting and oceanography.

5. Are there any exceptions to this principle?

There are a few exceptions to the density-temperature relationship, such as with water. As water reaches its freezing point, it becomes less dense, causing it to float on top of the denser cold water below. This is why ice floats on top of water rather than sinking to the bottom.

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