How does a whip break the sound barrier? (Slow Motion Shockwave formation) - Smarter Every Day 207
SmarterEveryDay2 HN recommenders · recommended in 2 months, 2019–2023
explainer · general · evergreen · 2019–2023 on HN
Smarter Every Day uses high-speed and Schlieren photography to show how a whip crack is a supersonic shockwave formed at the tip. It references academic papers on whip physics.
Recommended as the clearest footage of a whip tip going supersonic, and cited in shockwave discussions.
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3 comments from Hacker News
Fun fact, you can accelerate an almost-everyday object to supersonic speeds: whip tip [1,2]. 1. link 2. ▶ this video (very much recommended)
As mentioned by others, the photography technique looks like (and apparently is a software enabled variant of) Schlieren photography. This(1) is a neat example of an old school Schlieren set up capturing shockwave formation during whip cracks. I highly recommend it. (1) ▶ this video
Point taken. Thanks for the explanation, that helped me a achieve a deeper understanding & blew my mind. This animation of a tachyon goes well with your explanation: link If you look for it, you can observe this effect in the high speed Schlieren footage of a whip in this video ▶ this video (you can skip to around 8 minutes) It starts to disturb the air, then the shockwave overtakes the disturbance, so you can observe them in the flipped order if you're in the sound universe.