This is the sound of a very complex physics paper being written.

@aronegill

5 жыл бұрын

So mostly silence and a whip crack every now and then?

@BazilRat

5 жыл бұрын

Or some other loud noise. And then excited talking as everything starts to make sense.

@jayhawk1805

3 жыл бұрын

So any update on the paper being written? I would love to read it

@mattmobile

3 жыл бұрын

Could you make a giant whip on the moon that would launch things by letting go when at full speed? Just an idea.

@PurpleRain123453

3 жыл бұрын

@@mattmobile What you're describing is called a trebuchet.

I love the intense scrutiny and seeing the minds' "gear spinning" as y'all dig into the different perspectives and possibilities :D

@nvrumi

5 жыл бұрын

It's a really heady trip to work with a bunch of brains on a research problem. It is one of the things I miss about the research team I worked with.

@breadman32398

5 жыл бұрын

I personally don't like it when a team does that, I feel like things are getting rushed or overlooked.

@babaregi5934

5 жыл бұрын

Awww, just a bunch of whippersnappers!

You know how scientific papers are the highest standard where scientific results are published. In 2018 I find that old fashioned as there are so many richer ways of presenting the research process. There were times in my research where I could not replicate the experiment from papers alone because there was insufficient information to go on in the paper. It's be cool if scientific research could be published in video form as it is the richest data stream, but I guess we are stuck with the traditional paper format. I know that is not what you are trying to do here, but I got a really good idea about your experimental setup that would be hard to communicate in a paper. Anyway, looking forward to see how it all pans out!

@braa194332

5 жыл бұрын

It's been a recent trend (at least in climatology) to include supplementary material with papers that might be 100 pages long. In machine learning research they include source code for experiments on github and might upload their video to KZread.

@dylanpritchard4981

5 жыл бұрын

Seems like a no brainer honestly. But some people are stuck in tradition I guess.

@themasqueradingcow91

5 жыл бұрын

That's the point in supplementary material. Alas, some researchers are so overly protective of their methodologies that they are really difficult to get hold of! I needed one map from a researcher (the data points used and the meta data) which would take me months to do myself for my masters thesis. Bare in mind that the images and data is all publicly available, I just lack the computing resources. Trying to get hold of and convince the PI that it's just for a research thesis and nothing more is a nightmare! Luckily though, due to a lot of information from the planetary science community funded through tax payers, it is often publicly available and researchers all over forums trying to refine techniques and what not.

@braa194332

5 жыл бұрын

@@themasqueradingcow91 That's an interesting point: Open source vs. licenced scientific programs. The former depends on providing extra (premium) services to generate profit. The latter allows you to be the sole provider of that service, plus it allows me as a scientific programmer to create a name for my department in my organization and possibly convince admin to hire more ppl.

@ScientificLee

5 жыл бұрын

unfortunately you are regarded as crazy still if you do...I just showed magnetism creates spheres in real time...the ONLY force to be shown so far in science...by me :)...everyone says I must be a lunatic and where is my peer review, when the evidence is observable on video. They say its not happening !! I also follow God and so its double "insanity" insults for me...yet I am the only man to show the creation of a sphere by magnetism, with an explanation of how it works....4 years and 400 videos and people still say I am insane... most do when they hear where I say I got all this information...ah well...the electric universe and observational evidence are king. and God is proven :)

These videos have seriously gone up several levels in terms of quality of content and engineering principles recently. I cant wait to see what is next! P.S. as an acoustic engineer put your ear defenders on without the cap underneath (and possibly not upside down) and as a safety sally, a water bottle isn't a replacement for protective googles.

@smartereveryday

5 жыл бұрын

I didn't know which way was up. They were too fancy for me. I'm a foamies guy.

@candykanefpv98

5 жыл бұрын

burying your face in your elbow would be more protection than a water bottle lol.

@MrJdsenior

5 жыл бұрын

Yes, at a minimum, you need TWO. ;-)

You "dropped" Prince Rupert. :-p

@justinchadwick4509

5 жыл бұрын

Its okay, cats don't land on their tails.

Jeeze, this video and its companion on the main channel are some of the coolest things that I've seen in a _Long_ time! Fantastic work as always!!

@smartereveryday

5 жыл бұрын

Thanks! We try.

@PierceArner

5 жыл бұрын

@@smartereveryday You definitely succeed! Keep up the good work, and thanks for helping to make so many of us smarter every day!

Destin, Thank you so much for making this video!

@nvrumi

5 жыл бұрын

And thanks to you, April Jennifer Choi, for brining your skills to the party! Without the whip, there would be no video and no research!

@spamboli

5 жыл бұрын

how many times did you crack the whip? individually they "looked" easy, but it must have been an exhausting day

@AprilJenniferChoi

5 жыл бұрын

Somewhere around 50-60 trials.

@Zenpaper

5 жыл бұрын

April you are amazing and an inspiration!

@assaultpickle77

3 жыл бұрын

Oh, well hello there. Your physics and whip skills are amazing. Thank you for lending your time and talents into making this video and generating this calculatable science.

I never knew Prince Rupert was a cat.

@PavelPodesva

4 жыл бұрын

How exactly are Ruppert's drops made?

@glennosmond4306

4 жыл бұрын

he has royal blood... just a drop

now all you need is Mark Rober to make a device that cracks a whip perfectly every time!

@JochemKuijpers

5 жыл бұрын

I think they already have one of those: April.

@EclipseAtDusk

5 жыл бұрын

That would actually have to be a SUPER complex machine, given the amount of subtlety involved in cracking a whip. A lot of that is feel tbh, you have to get the whip moving JUST RIGHT to actually get it to crack. April can get it super consistently due to YEARS of experience and a detailed knowledge on the physics behind how it works, but building a robot to do it would be rather difficult. I have an idea for one that would mimic the motion needed for a side flick crack, but it would also need an entirely custom whip for that robot - each whip is going to move slightly differently, so as soon as you put a different whip on it, you would need to adjust A LOT to get it to crack consistently

@Green__Man

3 жыл бұрын

@@EclipseAtDusk idk man you see that robot that shoots hoops perfectly every time that's insane too, someone will do it it's only a matter of when

13:56 ; Excellent positioning of the parabolic compression wave in the field of view. Remember that it might help, but taper is not required. Forty years ago as a young engineering student, I wrote a research paper based on microphone recordings in an anechoic chamber for describing this structure for the formation of the wave-front. (My original hypothesis (like yours?) was that the shock wave would be perpendicular to the whip travel, during the change in tip direction.) Cylindrical whip cross-section (constant diameter line) seems more dependent on the back-stroke to focus the kinetic energy into the tip. The shock wave requires both speed and a physical cross-section discontinuity (tip). Larger mass lowers the speed, and a small discontinuity seems sufficient for efficient transfer of energy from the whip to the air. I also noticed that the compression wave causes what looks like chaotic displacement of the tassel fibers within the wave crest (which might be critical?). I am curious about the effect of the shape of the tassel on the efficiency of the shock wave formation; you only reported use of two tips: a 'standard' tassel and a ball (much too big for good transfer). However, more or fewer fibers, and the range of fiber length would seem to be parameters of the energy transfer. I presume that the adoption of a tassel by the sport was that it lasted better than blunt or mono-filament. That might tell you something about the fiber strains and energy dynamics in the transfer process. The sport probably also chose the whip length for practical reasons like the 'depth of field' for target acquisition, against efficient compression wave generation (although a good sharp crack might also be a 'fun' factor).

12:14 Safety water bottle for Destin.

@EisenFeuer

5 жыл бұрын

I never noticed that 😂

@wobblysauce

5 жыл бұрын

2 bits of plastic and an air gap.

@smartereveryday

5 жыл бұрын

I WAS SCARED OK?

@Tfin

5 жыл бұрын

Well, it _is_ a bullet on a string, after all.

@victornpb

5 жыл бұрын

plastic bottle is harder than a juicy soft eye ball, I would do the same

I love how much more apparent it becomes that air is a fluid when viewed in slow-mo through the schlieren

It's a pretty tranquil arm-movement for something at the end reaching the sound barrier. Amazing!

I'm really enjoying this, you dump all the clips in, we get to see all the stuff you do

What really impresses me about Destin is he doesn't seem to annoy anyone when he is filming all this stuff. That's some good people skills right there.

I am a AE and i could watch your channel all day keep up the great work my friend, i encourage my 12 year old daughter to watch your channel and she loves it , thank you.

Destin, I think that to fully appreciate the Smarter Every Day video about whip cracks people really should see this behind the scenes about it too. Great job on this. I look forward to hearing about the paper y'all write up.

This is SO satisfying! I can't wait to see/read a detailed analysis of the data.

These videos make my day so much, this is amazing and so interesting, keep up the amazing work Destin.

I love how there are always these papers being published on things the average person thinks is a completely solved issue in science. And even then a KZreadr can come along a few years later and meaningfully expand on it using an old technique and new technology. This is like the real world equivalent of Scotty or Geordi inventing new science each week to keep the warp engines running.

Amazing, as always, Destin! I think I'd happily watch every second of your experiments including the chat in the car before and after and everything. Excellent work.

I think it just clicked! You said something in the other video about the whip popper being "pulled" along after the shock wave. The way it works in my head is more like a rocket passing through Max Q: as the popper accelerates, it builds up pressure along the leading edge. The aerodynamic pressure builds and builds as it becomes transonic, but the pressure drops off once the popper is supersonic. This sudden drop in aerodynamic pressure coupled with the (more or less) constant acceleration of the rolling whip results in the acceleration of the popper building, plateauing and picking back up, which is what you noticed. That's so cool!!

These two videos are so much fun Destin. I smiled through both and am smiling still.

Fantastic work. It's really amazing seeing your teamwork, every one of you bringing your own unique expertise and tools set to the table. None of this would have worked without ALL of you completing each other.

Extremely insightful! Thanks Destin and all the scientific team!

Was waiting for this, thanks bossman

Ok. That last slow mo shot. Just the audio was worth the watch of the behind the scenes vid. Not to mention the epic content! So glad you did this!!

This was such a satisfying video to watch the data develop into knowledge. Great work Destin and friends!

Incredible, just incredible! Please keep posting behind the scenes videos

My favorite moment is at 7:02 when Destin says “So what we’re doing now is analysis. What we should do now is just catch more data.” And everyone nods. More data!

One of the best BTS videos so far. Love to see the excitement, joy and good energy in the room when everybody is so stoked about learning and understanding.

I love your approach to this problem and the way you thought to collect several kinds of data and analyse all of it.

Such great footage, my dude. Thanks.

Wow, brings back childhood memories. I was cracking a bull whip 30 years ago and I’m 43 now. It was a souvenir from a place called frontier town in Berlin Maryland. Even learned to pan for gold (fools gold that is) and had my mind spinning back then. It’s changed, but I spent hours at home in the back yard changing he length of the tip and sound of the whip learning it. To watch childhood theory’s and experiments get documented like this is amazing. I don’t even remember if I understood it was breaking the sound barrier when I was 13 years old.

This and the main whip video are some of the best youtube, no, video period I have every scene. So much going on. So much science. Very awesome. DFTBA!

This is not only great science... It's beautiful! Awesome research, and excellent video!

Incredible! I can’t wait to see the published analysis.

All that movement from 15:15 to 15:37 but she's just a statue the whole time.

@MmeHyraelle

5 жыл бұрын

It's actually beautiful how the human body can be :)

@_aullik

5 жыл бұрын

well that whole section is ~200ms so its a pretty small time frame.

@AdamJRichardson

5 жыл бұрын

Nice color grading on that too

@flysubcompact

5 жыл бұрын

That was a really cool shot showing how energy from the arm loaded the fat part of the whip, then the acceleration as energy was funneled through the decreasing mass.

@ociemitchell

5 жыл бұрын

And those lights are flashing 500 times a second.

Love the extra tape surprise at 7:25. :)

These were the best videos ever; just being able to see your research play out.

Awesome stuff! Thanks

7:21 - That image blew my mind! Love your presentations, SUBSCRIBED! Also, AMAZING that April never moved position and posture after the whip started to move in the 5000fps footage at the end.

Ok so the first video was impressive, but I think this video is either just as impressive, if not more. Absolutely amazing.

This was awesome Destin, April and others. Always been fascinated by whips. Learned so much and stirred up so many questions. One for example: Would the direction and timing of the barrier break be different when you aim the whip straight up and down

This is SO neat. I’m not standing on much ground when I ask this, as I’ve only taken an intro physics course and an exercise biomechanics course but first, it’s really cool to see the kinematic chain in slow motion of the torque production starting in the shoulder and traveling all the way to the tip of the whip. Secondly, I know things like tennis balls are fuzzy to increase surface area and a “barrier” of turbulence so that air rushing past that cap isn’t disturbed and the ball can glide and curve through the air easily with the magnus effect. It is interesting to see how the surface area of the tip decreased right as it approached the sound barrier that shot back apart after the “impact.” I feel like this is complicated a bit more because the knotted and beaded tips don’t produce as big of shockwaves. I wonder if this is due to their smaller and less interrupted surface areas which might slightly decrease their impact, in some way, as they break the sound barrier?

This is another Great video, Quality over quantity. Its Awesome how you assembled a team of experts and how many times, they where even shocked by the data and footage. KZreadrs like you and a handful of others keep me excited to learn, and push forward. I'm starting my senior year of Engineering Technology Management and because people like you, videos like this turned me from a College dropout factory worker to 13 years later packing a 3.85GPA. Thanks Buddy!

I'm really impressed by the amount of recoil in the whip: The one I made pretty much dropped like a dead snake. But that means your dynamics model must allow for the elasticity of the final 20% (or so) of the whip. Which may mean a single unified model may not be the best way to go. I'd advocate for separate continuous and discrete models, where the discrete model uses point masses connected by weightless springs. Then do something like simulated annealing to optimize the weight placement and spring values until good fidelity is obtained. The many test runs are an ideal source of training data! However, I suspect you'll find the mocap camera data will itself present problems, despite getting a good 3D reconstruction. Just looking, for example, at momentum will be difficult. (Well, that's what **I'd** find difficult, but I don't do this for a living.) If you ever get to do this again, I'd suggest putting an optical fiber down the center of the whip fed by a chirp laser. That should give you absolute bending radius as a function of distance, which should improve both models. Until the fiber breaks, of course.

So much HARD work, and smart people, of one of you are beautiful as well, thank you for your work. I enjoy it a lot.

This is so awesome!

WOW😲 This was as cool as the analysis vid❤❤❤THANK YOU 4 SHARING IT😃❤

Just a quick thumbs up for April! Tech is awesome but how impressive is her skill at getting the whip to crack in such a small area time after time! I bet she was bodily tired afterwards.

I love this channel!

Hands down one of your best videos yet! I know this is way old lol but the visual alone! And the amazing shot at 15:45 of the ropes velocity.. chefs kiss lol bravo👏 that was beautiful!!

Such a cool interesting thing to watch. Even without all the science and slow-mo, which is awesome, April just looks so cool with the whip.

The was so cool! Thanks!

Having seen this the biggest thing I took away was the slow mo at the end. The camera's were existing in their own timeframe as was the person, the whip and everything in the area. Just be an interesting concept if we could speed up or slow down our own perception and make it time relative. Imagine being able to speed up processing in our brain so you could watch an explosion slowly or see a threat coming and have eons to react. Or be able to slow down processing in order to zip through things.

The shot at 7:15 is so awesome bc you can see that the first point that goes supersonic, and generates the initial shock wave, is not at the tip of the whip, and the tip is being grabbed and carried by the shockwave after its begun. Would be really cool to see which variables (like whip length, weight, and taper) make a difference to the distance from the tip that the "inception point" of the shock wave happens. More experiments!!

Dustin have chosen the path of the samurai. He could devote channel his cat, and take way more subscribers then now, but he didn't. He prefer science, he's the hero youtube deserves)

@smartereveryday

5 жыл бұрын

You get it. I think..

@griel80

5 жыл бұрын

@@smartereveryday I understand, you hear that a lot, but that's a good moment to say thank to you. For many years i watched your videos, and for me it's hard to explain how valuable it is. Cats is pretty, but i'm realy changed my way of looking at the world, and thinking. You doing a really good job, i am a diffrent person now, and that a good changes which partly you have helped me to do.

Subscribed and hit the bell. Love the 2nd channel too!!!

Wow!!!!! The vid is hypnotising.

How about setting up a second schlieren-camera 90° to the existing to get some highspeed 3D Info from the tip? Could that work?

@gigaherz_

5 жыл бұрын

That sounds awesome, AND a nightmare to sync up, at the same time.

@no0ne000

5 жыл бұрын

Now you’re talking! I was just thinking how cool it was seeing “thickness” of the shockwave and how that is actually a 3D spherical section. With two or even three set-ups, you could get amazing full 3D modeling of everything; the whip, the shockwave, the heat vapors coming off the cord. That would be awesome!

@FesixGermany

5 жыл бұрын

I was just thinking about CT machines which work the same.

@smartereveryday

5 жыл бұрын

This setup actually can already get the 3D data.... it's hard to explain but all the info is there.

@tangneptune

5 жыл бұрын

@@smartereveryday Would be very interested to see this explained in a future video

those two vids are just mind blowing :-O

Awesome !!

Love that Schlieren photography, exactly what I wanted to see.

Destin I have one request. Never stop making videos... ever.

🤔 Choi's statement... About the threads having the air molecules around it, and the curving + acceleration increase of the whip end, compresses the gasses and the shock wave is the result of the imploding of those gasses; the crack sound is the fanning of the same threads that were just compressed... Awesome video!

Awesome 👍👍👍👍👍👍👍

That is very very cool, and a great way to end 2018. HNY Smarter Everyone!

so the tip gets faster because the momentum gets "concentrated" on the tip (instead of the whole whip moving, just the end moves) and because the end of the whip has less mass per length than the majority of the whip? (just me trying to understand this) you mentioned you guys wanted to make a "whip function" , did you try to make messurements with different whips? for example what were to happen when the whip has the same weight per length everywhere? or a point where that radically changes to see how the momentum gets transfered (how you showed in the other video as a red line)? im not a student and dont really know much about fluid dynamics and in generall dont have the know how but it really interests me and i love watching that stuff as it is something i wish to do in the future have a nice day

@thomasmaclean7465

5 жыл бұрын

So I think I heard describe something along the lines of conservation of momentum causing the smaller and smaller moving mass to accelerate; which makes sense to me. But then he ruined it in the intro by cracking a constant diameter string whip, for which the mass isn't decreasing any more: so why does it accelerate?

@d.devilcrusher6966

5 жыл бұрын

@@thomasmaclean7465 tried to whipcrack with a simple string and something that i noticed was that it was difficult to get the string to unroll like in the video shown, and i had to move my hand holding the string back instead of just stopping abruptly i would really like to see what happens exactly with other whips and why exactly the tip accelerates

@thomasmaclean7465

5 жыл бұрын

D. Devilcrusher I used to make whips as a child. I recall using string with some mass to it, like parachute cord. That would carry more momentum than a lightweight string. On the other hand, I don't recall them cracking nearly as loudly as April's.

@JohnnyWishbone85

4 жыл бұрын

For the period from just after the hand straightens out to just before the shockwave, you can (very roughly and imperfectly) conceive of the whip as the edge of a spinning disc of constant mass but decreasing diameter.

Destin, what do you think the behavior of a whip would be in a vacuum chamber? Would it help identify the difference between the tip breaking the sound barrier and not (subsonic)? What catches my attention is the way the tip seems to be pulled forward or unimpeded by the air after the shock wave cone is seen on the high speed.

I suspect the stiffness of the last few inches of the whip play an important roll in determining when the tip begins its peak acceleration. I've seen some whips that use several inches of stiff steel wire at the tip to aid in producing the crack. I think if the last few inches were infinitely... limp? the wave would propagate down the tip as a increasingly tiny loop all the way to the tip. The stiffness means at a certain point the last few inches break the loop formation and at that moment if the energy is sufficient the tip produces its shock wave / reaches maximum speed.

I JUSTin got Smarter Today. :-) Thanks.

OK, here's a question for thought. How does the beginning motion of the sonic boom producing movement of the whip compare to the movement of fracturing along a breaking Prince Rupert's Drop. How does the effect propagate along the length of the object? Not sure the best way to describe the thought.

Something about this topic makes me feel pretty amazed...and I'm not talking about the science guys!😅 Great content, great people, greater April👌🏼.

I just watched one of your videos and it was just like this only it had a different title and it had April in it? Or perhaps I should say it started out with April *OOOOHH!* I didn't realize that this was smarter every day channel number two until the end LOL

These two videos just stood out to me in the subscription feed, because they looked both particularly ordinary. I almost missed them. Did you ever consider putting an easily recognizable design (like your logo) on the thumbnail?

Wow amazing !!!!

Am I right in thinking this topic was first suggested by a viewer? This one of the most interesting videos ever done by SED. It's an example of a collaboration of the right technology, the right people, and the right attitude to science. My reaction to it was quite emotional which I find rather strange. What is it about the unimaginable truth that is so awe inspiring, which brings me to the verge of tears? Unimaginable truths - that's a good topic for "No Dumb Questions" also. The Theologian/Historian should debate this with the Scientist/Engineer.

It made me think that the popper is more to facilitate the delamination of the airflow. The beads you were using seemed to have a harder time because of the increased surface area meaning more energy was needed to create the shockwave. Some interesting physics and amazing footage. I would love to see a follow up with this.

WELL DONE !

What I find most interesting is that the thin tip of the whip (that last 6-8" piece) gets pushed along by the shockwave and never actually extends like the rest of the whip. In fact it ends up pulling the the whip back into the wake of the shackwave. You can see the moment that the tip goes from dragging the air along to being pushed along right when the shockwave forms. Incredible!

As you mentioned part of the idea is to blend the data from the motion capture alongside the high speed footage, does the use of the side arm affect how well you will be able to map out the motion of the very end of the whip? Im thinking in terms of the depth of the movement being much harder to perceive in the Schleiren image - you have reference points on the mirror which gives you a X and Y plane but measuring that Z axis has got to be difficult. In the vertical whipping scenario things could stay reasonably parallel and hopefully the amount of depth would be less of an issue. You've probably thought about this already and this really isnt my area of expertise but this video got me thinking a lot about how you can rebuild and model that motion out of the data afterwards.

A Science/Tech channel is never complete without cats.

Shoutout to that badass whip lady!! She made that look completely effortless, and very beautiful! Peace&Love&Light ☮☯️🕉

Would it be worth repeating with a non-tapered whip to see how much the taper is affecting the tip acceleration?

Hey Destin. At 15:36 it appears that the point where the whip breaks the sound barrier is in line with her shoulder. Is that always the case when she runs it overhand? Does it have something to do with that being the point where the energy starts from before traveling to the tip of the whip?

So I looked up the end card verse this time. Bravo.

You are making me want to go to engineering graduate school Destin. Dangerously interesting stuff

I think it's pretty interesting that at 13:55 there are shocks happening before the end of the whip. These shocks seems to cause a massive deceleration of a larger mass, accelerating the smaller mass more quickly. I think it would be pretty cool to see the acceleration or jerk curve along the length of the whip or as a function of cross sectional area.

Destin, you mentioned something in the main vid about an oddity regarding the shockwave/tassel interaction. With the multiple really good samples in this vid, it looks like the wave out runs the tassel. Or that the creation of the wave drops the forward momentum of the whip, with it then dragging the tassel forward. Is this something you are seeing as the data is analyzed?

Were you able to observe any effects of the drag lowering as you pass beyond the mach transition? THIS is a really cool piece of work, guys. EXCELLENT!! THIS is some of the better stuff the internet SHOULD consist of. Thumbed up, again. I am enjoying your series, and Domain of Science, below, makes a really good point! ;-) That velocity vector really does grow exponentially at the end.

Its cool to see little shock fronts forming on the knots behind the frayed end.

What wavelength light provides best resolution for that cinematography method? Also that looks really cool when flipbooked after being edge detected for each videoframe.

What really amazes me here is how in some shots the thing is moving fast enough to almost be too fast for the camera at 35k fps.... It almost seems to snap from one location to another between frames!

I had to explain that so many times to scepticals. Thanks for that demonstration! So obvious. To many rigids minds... I'm sure you know what i mean. (Obvious to you, so far for others...)

I wonder if you could crack a whip in zero G. It seems to me that the formation of that loop (you can see in the high speed 15:23) and it's closing at the end has something to do with the crack at the end. It also looks like gravity pulling the tip down forms that loop in the first place. So I wonder, without that loop, would it still crack?

14:37 pretty cool how that entire sequence took place from about 2540 ms to 3240 ms, so .7s.

Destin, what I find fascinating and haven't heard anyone talk about is the clear s-curve that develops with the tail of the whip. It's like the shock wave is behind the tail and blasts the tail forward, e.g., 13:01. The end of the tail outstrips the segment pulling it. Is it something obvious I don't know about? Why does that happen?

@feathered3167

5 жыл бұрын

I think it might have something to do with air resistance lessening after you get past mach 1.

@west

5 жыл бұрын

Feathered Maybe that is the reason, thanks! I specialize in electromagnetics and radar and never learned anything about fluids unfortunately.

@FelonyVideos

5 жыл бұрын

What you are seeing there is the moment the impedance of the air matches the impedance of the last inches of the whip. When that occurs, the ability of the whip to unroll, as it has done all the way up to that point, is matched by the load of the air being accelerated through the sound barrier. I think. ;-) After all, a whip's entire design and purpose is to impart energy into the air. The 'S' happens slightly after the whip has fulfilled it's design mission, as the air pushes back on the string dynamics, a slight recoil. It also means that ever so slight heavier tip mass should be used. The perfect impedence match would result in an L shape instead of an S. Notice how that last little knot comes to a complete stop, along with everything behind it? At that moment, the dynamics of the whip change to make it appear as a rigid solid fixed mass right at that knot. That's when the tip is forced to become rigid to the air as well. Notice how the until long motion stops and the end becomes like a rigid body? The S happens partly because the knot is either slightly too far distal, or the tip is slightly too light, pick your poison.

Great meowing, Destin!

12:14 Ahahahaha!!! Destin's improvised "bulletproof" goggles.