Puzzle: Which one will fill first?


Originally published at: http://boingboing.net/2017/08/03/flow.html


Woo I figured it out before seeing the animation.


None of them will ever fill. Both sides of all of them are open.


That is one of the most satisfying animations I’ve seen on these here internets.


Came to say that and also point out it depends on flow rate, if you dump enough in at the top your overflow path is different from the connection paths.



I actually think it depends on surface tension? I think K fills first if surface tension is high enough (or, shall we equivalently say, if pipe diameter is small enough), otherwise I correctly predicted F will fill first if you don’t account for surface tension at all.


I didn’t because I didn’t see the misdirection. Boo.


I almost got tricked by the blocked paths but I was paying attention for once.


In my and the puzzle’s creator’s defense: I read this on a smartphone, so it was kinda cramped. Could have made it out, but when I rewatched this on my 27" screen, it was much more obvious and I would’ve catched it by following the flow.


Yay for a 17" laptop screen.


Also, literally 4 a.m. in the morning in a dark bedroom.


Only if pipes and containers are very small, probably near a size where you’d have to consider whether capillary action comes into play.

Let’s just pretend that we’re all physicists and assume an ideal liquid flowing through frictionless containers and pipes, and the animation is spot on.



Somewhere, Bernoulli is… doing something.


Wow, really? That’s even more terrifying than I thought.


That’s the time on there, not minutes and seconds.


Not pictured: engineers actually building stuff, using math, physics, chemistry, biology… sometimes even psychology and sociology when we need to circumvent the beancounters.


Among other things, pinching the behinds of people sitting on underengineered park benches.


Also not there - us geologists hitting everything with hammers*

*which, when you think about it, is just what physicists do in the Large Hadron Collider.