The bizarre ripples that form in a stream of water

I noticed that when I obstruct a laminar flow of water I get these ripples forming upstream like a standing wave. Here's my attempt to capture them on film and to explain them. It might have something to do with Rayleigh-Plateau instability.

12 min - How Things Work - Steve Mould

More: How It Works documentaries

Read Deeper: How It Works

1. The Way Things Work Now by David Macaulay (4.3/5) - View on Amazon
2. How Things Work by Louis A. Bloomfield - View on Amazon
3. Thing Explainer by Randall Munroe (4.2/5) - View on Amazon
4. What If? by Randall Munroe (4.3/5) - View on Amazon

Watch Next

• Most People Don't Know How Bikes Work (11 min, Veritasium)
• The Insane Engineering of MRI Machines (18 min, Real Engineering)
• Why Are There so Many Types of Screws?! (8 min, Real Engineering)
• How the Germans Measured Milliseconds MECHANICALLY - Smarter Every Day 283 (17 min, Smarter Every Day)
• How the Warhead on the AIM-9 Sidewinder Works - Smarter Every Day 282 (8 min, Smarter Every Day)
• The "Impossible Torpedo" was real (17 min, Steve Mould)
• How petrol pumps know when to turn themselves off (14 min, Steve Mould)
• .50 Cal vs Ballistic Window HARDCORE Slow Mo - Smarter Every Day 187 (9 min, Smarter Every Day)