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Hot water freezes faster than cold water (Mpemba Effect)

math.ucr.edu

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Re: Hot water freezes faster than cold water (Mpemba Effect)

#11

Post by sharkfish »

whacked_new wrote: post #6
sharkfish wrote: post #5

My father showed me how much faster hot water freezes in an experiment we did when I was a kid. How many of us owe our fathers for what seems to be innate curiosity now that we are adults :)

And/or you inherited the curiosity trait.

Or the "prove your mom wrong" trait. That seemed to be his motivation, heh-heh.

Re: Hot water freezes faster than cold water (Mpemba Effect)

#12

Post by maximilian »

sharkfish wrote: post #5

My father showed me how much faster hot water freezes in an experiment we did when I was a kid. How many of us owe our fathers for what seems to be innate curiosity now that we are adults :)

I've done it a bunch of times and never had hot water freeze faster. How did you (or your dad) set it up?

Re: Hot water freezes faster than cold water (Mpemba Effect)

#13

Post by delackner »

ars wrote: post #9
cjc wrote: post #4

Except under very specific conditions, this is NOT TRUE. Do not fill your ice cube trays with hot water thinking it will freeze faster.

Are you sure about that? Maybe I should try it. The article certainly contradicts you.

Indeed, cjc sounds like someone who has already tried this at home, right? What circumstances are different between ice cube trays and ice cream mixture? High surface area comes to mind. In the article the experiments described all involve volumes of water (or ice cream goo) that are in containers with low surface area to volume. SA and Volume do not scale linearly, thus the heat exchange rate would be faster for the ice cube trays. Of course, TRYING it out would not hurt. Several hundred years worth of scientists seem to have laughed at previous experimental results out of some egotistical belief that experimental results passed down from history are fairy tales.
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