A Physics Professor Bet Me $10,000 I'm Wrong on HackerTube: recommended by 3 Hacker News commenters across 3 separate months, 2021–2023.
explainer · evergreen
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.
“The small demonstration that made it click for me is from that video”
8 Hacker News comments link this video. Each one links back to its thread.
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.
in “DDWFTTW Vehicle Analysis (2013)” · View on HN
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.
in “A wind-powered vehicle that can travel twice as fast as the wind itself” · View on HN
Original video triggering the bet for context: [link] Video discussing the bet and going over criticism: ▶ this video Veritasium is a great YouTube channel.
in “Science YouTuber Wins $10k Bet with Physicist” · View on HN
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
in “World's fastest sailboat: Two wild designs hit the water for testing” · View on HN
Dead fish swimming upstream .. Reminds me a bit of this: a wind-powered vehicle than can accelerate directly into the wind... ▶ this video
in “The swimming of a dead fish (2018)” · View on HN
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
in “A wind-powered vehicle that can travel twice as fast as the wind itself” · View on HN
The original Veritasium video [link] The video of the bet and the further explanations - ▶ this video -- at 13:28 is an example without aerodynamics.
in “A wind-powered vehicle that can travel twice as fast as the wind itself” · View on HN
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
in “A wind-powered vehicle that can travel twice as fast as the wind itself” · View on HN