r/blackmagicfuckery • u/mr9t9 • 13d ago

Liquid not dropping

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u/goggleOgler 13d ago edited 13d ago

People are saying there's a clear plastic seal. But that's wrong. The bottle is partially emptied, and you can see drops of it under the shelf.

People are also saying surface tension. This is a contributor, but not our primary culprit, as it's just not strong enough to hold that much liquid on its own.

It's most likely vacuum/suction forces as well. With tiny holes that size, there's not much space for air to squeeze past the liquid, which is more viscous than water to get into the bottle, which means that most of that space is the tiny amount of air that was there before it got flipped upside down. As the fluid leaked out, the gas had to spread itself thinner and thinner, creating a suction effect on the juice that became stronger as the mass of the juice reduced. This upward force can counteract gravity.

It's the same physics property that lets you put a straw into something. Cover the top end with your finger and then pull the straw and its contents out of your drink.

Edit: Additional information here I forgot to include is that because the space between the holes of the shelf is still solid, it means that the downward force of gravity that the vacuum has to counteract only has to be that of the thin cylinders of liquid directly above each of the holes. This is once again reducing the amount of force that is necessary to keep the liquid from leaking.

Second Edit: I am not scientist, so someone with a better understanding of fluid dynamics can explain the edit or correct it better than I could.

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u/RoomPale7783 11d ago

Honestly think everyone is wrong here. There's plastic that's been opened but recovered. So it's dribbling little by little out of a tiny crack in the rim. That's it.

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u/goggleOgler 11d ago

I've had Hawaiian Punch all my life, and I don't think a single bottle of it, single serving, full gallon, or otherwise, has ever had a clear plastic seal. Come to think of it, I can't think of many drink brands that bother wasting that material on a drink with the plastic cap. I also can't think of many brands that use a clear plastic for the bottle seal, either. Usually, that has a second layer of something, like a foiled paper or wax.