We previously wrote about a lighthearted bet between UCLA physics professor Alexander Kusenko and science communicator and founder of the Veritasium YouTube channel Derek Muller. The Blackbird, a prototype wind-powered land yacht, was the subject of disagreement between these two men. The vehicle's ability to go faster than the wind that pushes it is perplexing.
Muller published a video in which he tested the blackbird and gave an explanation. However, Kusenko got in touch to express his displeasure with the explanation because it did not set well with him. The wager was made after some back and forth.
The wind shifts, according to Kusenko, explaining the phenomenon that seems paradoxical. When the speed of the car is measured against the wind, it appears to be moving faster but is actually decelerating as a result of a strong wind gust pushing it to a greater speed and then gradually calming down. Additionally, the wind speed at the propeller's height may be higher than the wind speed at the height at which it was measured.
In the subsequent video describing the wager, Muller stated, "I'm pleased about this bet because if I am wrong then I want to know."
"Getting to the truth is the main goal of the channel,"
Muller went out to address Kusenko's concern while also offering a more thorough justification. Data from numerous testing have demonstrated that the vehicle continues to move faster than the wind even at the height of the propeller and that the Blackbird was still gaining speed as it broke the previous record of 2.8 times the wind.
So how does it function? Most people are mistaken about how the propeller functions. Muller notes that it pushes air backward more like a fan than a windmill. The propeller is turned by the wheels so that it propels the vehicle ahead as it gains speed. The Blackbird travels forward despite the wheels being slowed down by friction because of the propeller's much stronger push.
Muller continues to explain how this method also occurs in situations unrelated to wind-powered vehicles. He even persuaded fellow YouTuber Xyla Foxlin to create a model (or several, in fact) that could display the downwind cart approach while running on a treadmill. And Foxlin's cart actually performed as predicted, accelerating more quickly than the treadmill.
Professor Kusenko has now accepted the wager and sent me $10,000. In the YouTube video, Muller stated, "I want to applaud him for being a man of honour and altering his position in light of the information presented.
As part of a competition described on the Veritasium channel, the winnings of the wager will now be given to other science communicators.
0 Comments