Which freezes faster?......hot water or cold water?
2006-08-03 19:53:40 · 20 answers · asked by ghostguff 2 in Science & Mathematics ➔ Chemistry
it depends on many situational factors ...
but when hot water freezes faster than cold water under identical conditions, it is known as the MPEMBA EFFECT.
this phenomenon was described very early in history, even by Aristotle, but Mpemba, a high school student in Tanzania, was the first person to confirm the anomaly during an experiment in 1969.
2006-08-03 20:09:32 · answer #1 · answered by tanmei 3 · 3⤊ 0⤋
Cold water will always freeze faster under the same conditions than hot. What would happen in a parallel universe when the racing hot water reaches the temperature of the cold water cooling down? Ignore our physical reality and still cool faster?
2006-08-04 08:33:52 · answer #2 · answered by ppellet 3 · 0⤊ 0⤋
Place a plastic cup of hot water, and one of cold water, side by side in the freezer.
You'll see that cold water freezes faster.
Why? Because it has to shed less heat to reach 32 degrees F.
However, the hotter the water, the faster its temperature will drop. This is what makes some people think hot water freezes faster.
What they forget is that hot water has to cool more, too.
2006-08-04 03:00:09 · answer #3 · answered by Danny R 1 · 0⤊ 0⤋
Cold water freezes faster because it's closer to freezing point.
Hot water needs some extra time to become cold. Suppose x is the time that cold water needs to freeze. Hot water needs x+y time (where y is the time needed for hot water to become cold). So, it's obvious that x+y>x.
2006-08-04 04:51:28 · answer #4 · answered by frog 1 · 0⤊ 0⤋
Cold. 32 degrees Fahrenheit is freezing temperature. Hot water takes longer to cool down. The theory that hot water freezes faster is a myth. So is the the theory that cold water boils faster.
2006-08-04 02:59:59 · answer #5 · answered by Wendy 3 · 0⤊ 0⤋
It depends on the condition- most importantly, how hot the hot water is. The theory is that if the water is around boiling point, a lot of it will evaporate and then cool down so there is less water to freeze.
2006-08-04 04:18:58 · answer #6 · answered by stage_poi 4 · 0⤊ 0⤋
Hot water.
2006-08-04 02:58:20 · answer #7 · answered by cricket 3 · 0⤊ 0⤋
Hot Water, I heard people asking this question too many times on Yahoo! Answers.
2006-08-04 03:13:37 · answer #8 · answered by Dimples 6 · 0⤊ 0⤋
you need less energy to freeze cold water than you need freezing hot water... Therefore, in a realistic environment, the cold water freezes first.
2006-08-04 02:58:46 · answer #9 · answered by Anonymous · 0⤊ 0⤋
i think if you put a hot cup of water and a cold cup of water in a freezer they will doth freez at the same time.
2006-08-04 03:09:41 · answer #10 · answered by Jerry 2 · 0⤊ 0⤋