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Comment by beanlog | Hacker News Reader

Why am I unable to find a single good video on the internet demonstrating the mpemba effect occuring? If people were really heating their water before freezing it in Aristotle's time, then this shouldn't require any precise technology to reproduce. The article addresses the fact that this seems very easy to test, but then doesn't explain why no one's reproduced it on camera.

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https://www.youtube.com/watch?v=SkH2iX0rx8U

I see, so the answer is that the effect doesn't exist but it's easy to think it does by not controlling for a variable very well.

Because it’s bullshit. People who observed this supposed effect don’t even bother to place both containers in the same fridge at the same time (so it’s not affected by the thermostat’s timing) nor do they weigh the ice afterwards.

Youtube is full of videos showing how boiling water freezing mid air in very cold temps

https://youtu.be/pTf7X_COAvM

https://youtu.be/7syogXi5LIY

But there is no frozen water. You can see a lot of steam being carried away by the wind and water droplets leaving trails but no ice or snow.

What happens if you do that with cold water? Also, there's no indication of the water freezing. How would you tell if the water is freezing or not once it's landed in the snow?

Yes, the only videos demonstrations involve throwing the water into the air, but nothing in this article or the Wikipedia page about the effect suggest that throwing the water is necessary for the effect to occur. I don't even know where these people got the idea to do the experiment that way. Their result is way less interesting because it can be explained by surface area.

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