How does a whip break the sound barrier? (Slow Motion Shockwave formation) - Smarter Every Day 207

SmarterEveryDay2 HN recommenders · 2019–2023
6.5M views · explainer · evergreen · Uploaded 2018-12-28

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.

Watch on YouTube

3 comments from Hacker News

@wolfram742019 · in “Nasa captures images of supersonic shockwaves”

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) [VIDEO]

Strongly recommendsView on HN
@nuccy2021 · in “Supersonic Trebuchet”

Fun fact, you can accelerate an almost-everyday object to supersonic speeds: whip tip [1,2]. 1. [LINK] 2. [VIDEO] (very much recommended)

Strongly recommendsView on HN
@maxbond2023 · in “Sabine Hossenfelder: I think faster than light travel is possible. Here's why”

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 [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.