Water, is it faster to pour hot water into cold water, or is it faster to pour cold water into hot w

I think that since the water is poured into another place, the same volume, the initial kinetic energy is enough for them to mix well, and the density difference between hot and cold water has little effect on the mixing in this case (in other cases, the density difference may dominate the mixing effect, for example, the initial state of two liquids is layered and stationary). So whether you pour hot water into cold water or cold water into hot water, there is no difference in the speed of cooling. In the above answer, when it comes to heat exchange with air and hot water cups, I just want to say that the heat exchange with air is negligible in such a short time of pouring water, and it is simply not an engineer to take the time to think about it.

The hot water cup itself is for thermal insulation, and the heat capacity of the cup itself is not large, so considering that this kind of thing may have a 1 in 10,000 effect on the cold and heat exchange rate. <>

If it can be assumed that the two containers are almost the same, there is an infinite amount of hot and cold water, and the heat storage density of the container is infinitely small, that is, the influence of other objective factors is eliminated. I think hot water poured cold water equalizes faster.

Rationale: air convection; Hot water at high temperature tends to be relatively low in density, and in the process of addition, the relatively high density of cold water can easily "seep" into the hot water for convection. Since the impulse generated by gravity will overcome the negligible "buoyancy" of the hot water, and the hot water falling into the cold water will quickly be swallowed up and dismembered by the cold water (cold water infiltration), so there will be no stratification of "hot water on the top and cold water on the bottom" in the process, and this illusion is just an illusion brought to you by life experience.

1. When the hot and cold water are put in at the same time, the cold water will not immediately cool down significantly, because the heat of the hot water will increase the temperature in the refrigerator. Because the hot water has a large temperature and dust signal difference with the air in the refrigerator, the hot water cools down quickly until it is equivalent to the cold water. Second, the same volume of hot water and cold water, the density of hot water is smaller than that of cold water, so the quality of hot water is smaller than cold water, and when the temperature of hot water and cold water is equal, the cooling speed of hot water will be faster than that of cold water.

So the hot water freezes first.

Cold boiled water refers to the water that is cooled after boiling, which is the most drunk edible water in ordinary life, light and tasteless, extremely ordinary, but has a very important conditioning effect on the physiological mechanism of the human body;

Cold boiled water not only quenches thirst, but also most easily promotes metabolism, regulates body temperature, increases hemoglobin content in the blood, enhances the body's immune function, and improves the body's ability to resist diseases.

In addition, water also has the physiological function of substances contained in beverages but does not have, water can regulate body temperature, so that the temperature of the human body does not fluctuate too much.

Water is a lubricant for friction between human tissues, with strong solubility, a variety of inorganic and organic substances are easily soluble in water, and metabolic wastes in the body are easily removed to the body under the action of water, with intestinal cleansing function.

Cold boiled water can also improve the activity of lactate dehydrogenase in the organs, which is conducive to quickly reducing the "fatigue hormone", that is, lactic acid, accumulated in the muscles, so as to achieve the purpose of eliminating fatigue and rejuvenating the spirit.