Why Your Pee Looks Like A Chain

Have you noticed the shape of your urine stream when you pee? It does this twisty undulating thing. But why? And why do the same waves appear when you pour a liquid from a container?

Here's my video featuring Rayleigh instability:

Here's my video about the Lattice Boltzmann Method:

The fake medical advice at the end comes courtesy of not-fake Doctor Rohin Francis. This is his excellent channel:

Here are a couple of good videos on laminar flow:

Image and video credits:
The video of water floating in microgravity is by NASA
The Lattice Boltzmann animation is by Richard Sear

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[ElectroBOOM]

No literature on it? Then let's call it Mould Effect #2!

[Masquerola]

SmarterEveryDay: Laminar flow is my favorite!
Veritasium: No, turbulent flow is better!

Steve Mould: why is my pee a chain

"Let's approach as closely as possible to the Platonic Ideal of a stream of pis--"

This is the single greatest line in the entire history of YouTube videos.

[MystDawg]

As a huge fan of both physics and piss this appeals to me greatly

[tdude]

Rohin looking at picture of Matt, and his phone line being physically disconnected are the best parts of the bit. Solid colab :)

[FanOfAwesome]

The shape resembles a chain. I'd call it a water chain, and address each "pinch" as a waterlink.

[Love-and-Salt]

This man has just become the pouring liquid expert at this point and I’m here for this extremely niche content

[latergator]

I love how you perfectly emulate the “disheveled but still functioning look”

[jekizer]

"This video is not about laminar flow."
> Destin has left the chat

[terrygoyan]

Wife: "What the heck are you doing in the bathroom?"
Man: "Experimenting!"

[Siberius-]

0:20 - "PUSHING water out of your body". That's interesting phrasing, but less interesting since I already found out that many people can't pee by just relaxing and letting it flow out by itself (unless they are busting). They have to actually push, to expel the liquids, otherwise nothing comes out. Now, to get the last tiny bit out, one will have to push a bit either way, so both sides have a bit of each other's situation going on to a minor degree lol. How beautiful.

[WhatColourIsYourBugatti_]

10:53 Casually staring at a picture of Matt Parker, then picking up a telephone that isn’t even connected. Feels like the start of an adult film...

[Chaunton]

"Let's approach, as closely as possible, the platonic ideal of a stream of pi-."
Love it.

[kaidenschmidt]

“The platonic IDEAL of a stream of pi-“

[paullove]

Ive always considered myself to be of an analytical mindset. I'm always looking at things and trying to understand how they work. But the problem I always have is then explaining what I am now able to understand. But I love that your out here doing the homework for us and really answering the big questions that need answering. Love your channel. I look forward to learning something new Everytime I click on one.

[GediMini]

the British YouTuber cinematic universe is getting out of hand... And I love it!

[davisdiercks]

"We need laminar fl-"
* Destin materializes out of thin air *
You summoned me?

[Ruffaloo]

Quarantine day 336: "Why does my pee look like a chain?"

[timelsen]

Steve Mould is the science bomb of all You Tube. He always has the unusual not found anywhere, with intuitive explanations easy to follow. All schools should study Steve's work.

[Elitematt]

Some say if you repeat "Laminar flow" three times in a mirror, Destin appear behind you...