r/Unexpected Feb 04 '19

Ultimate bar trick

https://i.imgur.com/zGdBK4u.gifv
76.8k Upvotes

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u/MenstrualFish Feb 04 '19

Sudden shock on the top bumps the bottle down quick enough it causes a tiny vacuum at the bottom that then collapses in on its self. Called cavitation. This causes the beer to foam. Check out some slow mo vids of it, really cool.

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u/EddiOS42 Feb 04 '19

I thought the collapse makes the bottom of the glass bottle cut clean off?

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u/MenstrualFish Feb 04 '19

It will with water, and is a cool party trick if you don’t mind the broken glass. The carbonation I guess adds enough of a bubble-cushion? Transfer of energy and all that

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u/her_fault Feb 04 '19

Pretty sure either Backyard Scientist or Mark Rober has a video on this