A Physics Professor Bet Me $10,000 I'm Wrong
Veritasium3 HN recommenders · recommended in 3 months, 2021–2023
explainer · general · evergreen · 2021–2023 on HN
Veritasium recounts a $10,000 bet with a UCLA physics professor over whether a vehicle can travel downwind faster than the wind. He presents the professor's reasoning and demonstrations, including one without aerodynamics.
Linked as clear demonstrations that make the counterintuitive faster-than-wind result click.
Up next
3 mo on HNRisking My Life To Settle A Physics Debate
Veritasium
5 HN recommender · 2021–2023
13 mo on HNMIT's Pathway to Fusion Energy (IAP 2017) - Zach Hartwig
MIT Plasma Science and Fusion Center
16 HN recommender · 2017–2023
3 mo on HNRetroAhoy: The Secret of Monkey Island
Ahoy
3 HN recommender · 2020–2022
15 mo on HNBut what is the Fourier Transform? A visual introduction.
3Blue1Brown
16 HN recommender · 2018–2025
7 mo on HNCppCon 2017: Titus Winters “C++ as a "Live at Head" Language”
CppCon
7 HN recommender · 2017–2022
5 mo on HNThese Stupid Trucks are Literally Killing Us
Not Just Bikes
11 HN recommender · 2023–2026
8 mo on HNI bought 1000 meters of wire to settle a physics debate
AlphaPhoenix
8 HN recommender · 2021–2026
8 mo on HNThe Speed of Light is NOT About Light
PBS Space Time
8 HN recommender · 2017–2023
7 mo on HNWhy No One Has Measured The Speed Of Light
Veritasium
6 HN recommender · 2020–2024
6 mo on HNRichard Feynman - The.Character of Physical Law - Part 1 The Law of Gravitation (full version)
Tinkerin' Thinkers
6 HN recommender · 2013–2022
6 mo on HNHD Feynman: FUN TO IMAGINE complete (with optional Chinese subtitles)
Christopher Sykes
4 HN recommender · 2021–2025
6 mo on HNA new way to visualize General Relativity
ScienceClic English
8 HN recommender · 2020–2026
8 comments from Hacker News
Derek from the YouTube channel Veritasium made two interesting videos about this vehicle. link ▶ this video They go into some nice detail about why the physics works out the way it does.
The small demonstration that made it click for me is from that video: ▶ this video This is exactly what the blackbird does, only with a propeller pushing air in place of the big wheel, and it's a much clearer and simpler demonstration of the same idea, which you can trivially verify.
Original video triggering the bet for context: link Video discussing the bet and going over criticism: ▶ this video Veritasium is a great YouTube channel.
I doubt this is how sailboats are doing it (if they're doing it) but one way is (I think) to make the airfoil itself cut across the wind while the "boat" goes straight downwind. See these videos: link ▶ this video
Dead fish swimming upstream .. Reminds me a bit of this: a wind-powered vehicle than can accelerate directly into the wind... ▶ this video
The most surprising thing here is that someone on Twitter made a bet, lost the bet, and then actually paid said bet. Playing devil's advocate here a little: The whole machine is very counter-intuitive, and I can see how I myself may disbelieve it if not for the irrefutable demonstration(s)[0]. [0] ▶ this video
The original Veritasium video link The video of the bet and the further explanations - ▶ this video -- at 13:28 is an example without aerodynamics.
The professor's reasoning is near the start of the video about the bet [1]. Basically they thought the makers of blackbird were fooling themselves (e.g. measuring slower wind at the bottom of the car vs the top of the propeller, or getting pushed above the average wind speed by gusts then selectively reporting). 1: ▶ this video