Does hot water really freeze faster than cold water?

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SUMMARY

The discussion centers on the Mpemba effect, which posits that hot water can freeze faster than cold water under certain conditions. A woman observed this phenomenon while timing the freezing of ice trays, prompting her engineer husband to initially dismiss her claim. The conversation highlights factors such as the rate of heat loss and surface temperature dynamics that contribute to this counterintuitive result. For a comprehensive understanding, participants are directed to an external FAQ that elaborates on the Mpemba effect.

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Rocket_guy
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1. A woman informs her engineer husband that "hot water will freeze faster than cold water". He calls this statement nonsense. She answers by saying that she had actually timed the freezing process for ice trays in the home refrigerator and found that the hot water does indeed freeze faster. As a friend, you are asked to settle the argument. Is there a logical explanation for the woman's observation?



2. NONE



3. Is it becoz of the faster rate of heat loss from hot water as compared to cold water? But water freezes after a certain temeprature .. the hot water will first cool to lower temperature as of the cold water then freeze thus taking more time! Or is it that the surface temp. of the hot water will fall faster and thus may seem that the ice was made faster out of the hot water? Any ideas??
 
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What you are referring to is commonly known as the Mpemba effect. I'm referring you to an external FAQ, not because I can't be bothered to answer your question, but the link discusses the topic comprehensively and you'll get a lot more out of it than if I were to type a few words here.

http://math.ucr.edu/home/baez/physics/General/hot_water.html
 
Hey .. thanks .. that was a nice explanation!
 

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