The mysterious isochronous curve

[@OriginalCoastalDistancing]

I was just saying to the wife the other day, “You know what we could really use about now? A demonstration of the unique properties of the isochronous curve.” And whaddaya know, here it is. Saved our marriage.

[@rogueuniversities6866]

Hehe

[@matthewturner9109]

lmao

[@johnreynolds6369]

Same thing here. There’s a coincidence/

[@jpshy1130]

Damn what are the odds

[@Tropicpapi]

Story time?

[@MadMonkey572]

I don't know how I got here but I'm glad I did.

[@CuriosityShow]

Many thanks - hundreds more like it at kzbin.info - spread the word - Rob

[@lillyfingers]

Me too! have to show my son when he gets home!

[@MicrobyteAlan]

Me too

[@sporehux8344]

Either youTube knows what I like, or I like any random thing that's recommended to me.

[@Madmas27]

Same! Blew my mind, subscribed :)

[@timothyrepp4259]

Turns out the fastest route between two points isn’t a straight line.It’s an isochronous curve.

[@lifes2short]

Tell that to my physics teacher 🤣 Lol in a downward/gravity driven situation. Then yes, on the horizontal axis, as we move as humans then no lol

[@tituslafrombois1164]

Well, "fastest" in the sense of least distance traveled, yes, straight line is the answer. The ball bearing on the curve only got there faster because it started at a much stepper angle and so built up momentum quicker.

[@hangukhiphop]

assuming there's a force like gravity accelerating the object in only one dimension edit: that's actually the brachistochrone, which is a similar curve in the cycloid family the isochronous also belongs to

[@xxnocturnaltank859]

I think he was just joking guys lmao

[@AaronMorel01]

"The shortest path was a detour”

[@jenchast]

I’ve missed calm relaxed explaining shows without any hype or screaming or over-the-top nonsense just teach quietly and affectively

[@daniellebcooper7160]

well said.

[@martynridley3671]

'effectively'

[@TheComicChild]

* BEGINGS BLARING BILL NYE THE SCIENCE GUY *

[@Maximillian-00]

those are called children's youtube videos.

[@Tore_Lund]

Today, such an educational program would be made with computer graphics. It would still be as useful for a demonstration, but there is something about watching real cardboard and ball bearings. You are watching reality, not an animation of a claim. It is real and easier to remember, so more effective for education.

[@Eis_Bear]

The isochronous curve was also an important discovery for the advance in timekeeping, Christiaan Huygens invented the cycloid pendulum which doesn't simply travel part of a circle but rather travels in an isochronous curve thus keeping the same timing regardless of momentum.

[@nicholkid]

brilliant

[@bobweiram6321]

I was thinking about a practical application for the isochronous curve in particle accelerators after watching the video. Did a quick Google search and found out some cyclotrons already use it in their design. Damn! They beat me to it.

[@WadeWilsonDP]

@Arcadetron Racing A pendulum is the thing you see in a grandfather clock that swings back and forth. A clock is a mechanical device used to keep track of time based on the rotation of the Earth. It takes approximately 24 hours for the Earth to make a full rotation and we divide this up into 2 12 hour segments. A typical clock has 12 numbers on it, depicting the 12 hours of each half of the day. We divide these up into 60 segments that we call "minutes" to keep track of shorter lengths of time.

[@citizenoftheninthdivision]

@@WadeWilsonDP Hahaha nice.

[@mrbojangles9841]

Christian Huygens must have been a Republican. They're the smartest people.

[@audrablue515]

I used to love this show when I was a kid. I couldn’t get enough of all the fascinating experiments they did. I’m 55 years old now and work in a call centre so obviously the science bug didn’t hit me hard enough lol

[@monchoglu]

Work doesn't define who you are, if you enjoyed this show you are a scientist

[@zo1dberg]

Nothing wrong with occupying your free time watching this over watching Netflix, and it's never too late to be bitten by the science bug. I used to love this show as a kid too!

[@drivingintothedesertuntilt3202]

scientists are c u n t s

[@pikpik42]

I guess the idea of early science was to make wisdom and knowledge accessible to everyone so everybody can understand the world by their own, since it's scientific proven and understandable through experience and explanation. This is what impressed me, as a kid and as an adult. The love of and for explaining and understanding the world you are in. No wonder we love this :)

[@davedaniels8211]

@@drivingintothedesertuntilt3202 varum ?

[@rjb204]

Thank you, KZbin for showing me this. Before this video, I thought my life was a downhill slide. Now I know its on this damn curve.

[@fern9760]

it gets shittier faster?

[@JpOcDenver]

Should be headed upwards anytime now!

[@McClurg08]

@@JpOcDenver FeelsGoodMan

[@idratherbeoutdoors3753]

That's one of the funniest comments I've ever read. Painfully relevant though.

[@chriskearney1745]

Isochronic fatigue?

[@tinfoilhat1417]

It's crazy to think that my dad used to watch this on television when he was a kid back in the 70s. Now I'm in senior year and know why he loved it so much.

[@castleanthrax1833]

You are quite fortunate to have re-discovered some iconic Australian television. It's a real shame that this show ceased production. I could never understand why, as the ABC produces some real rubbish TV. This was a gem. Thank you KZbin.

[@analcommando1124]

@@castleanthrax1833 it was on nine

[@castleanthrax1833]

@@analcommando1124 Give me a break. I was a kid, and it was a long time ago. Edit: I guess that explains why the ABC doesn't make it anymore.

[@Holden308]

@@castleanthrax1833 ... The Curiosity Show was made by Banksia Productions in Adelaide for the Nine Network and was presented by Dr. Rob Morrison (seen in this clip) and Dean Hutton.

[@castleanthrax1833]

@@Holden308 Yes I know. It's already been pointed out and acknowledged by me on the replies immediately before yours. Thank you.

[@Frogglin]

What I particularly enjoy about the Curiosity Show is the clear way everything is presented without talking down to the audience. Rob and Deane really have a fabulous knack for presenting.

[@CuriosityShow]

Many thanks indeed. Please spread the word about kzbin.info - Rob

[@Frogglin]

Oh believe me I have :D I was so excited to see these pop up on KZbin. Still fascinating all these years later.

[@heyidiot]

But FFS, what have you actually LEARNED from this? This is the geometrical equivalent of a circus freak show!

[@CuriosityShow]

An absolute pleasure. Lots more at kzbin.info - please spread the word - Rob

[@90210au]

@@CuriosityShow if u r the real Rob then u should know u inspired a whole generation of kids to love science. I think science shows like the curiosity show are what inspired me to pursue a career in science

[@pintificate]

This curve holds a lot of secrets. The area of the enclosed cycloid (segment) is three times the area of the circle used to create it, and the length of the curve is four times the diameter of the circle. So the Pi value of a rolling circle is _four_ . You can create this cycloid by tilting a circle 57.518 degrees from the vertical, and then photograph the top half of the tilted circle. It's the only isochronous curve. Somehow it seems to be aware that it is supposed to be a circle.There's something in this, but I don't know what. .

[@johnbarron4265]

But wait. The projection of a tilted circle is an ellipse.

[@onomatopoeia2223]

🤯🤯🤯

[@Fazmagarical]

Quantum.

[@raynic1173]

Holy time space Jim, that's exactly how particles behave in the warp drive.

[@throngcleaver]

@@johnbarron4265 The isochronous curve is half of an ellipse. A very special ellipse, at the angle james west mentioned.

[@ltsecondincomand]

That rusty tin though, back when contents of a show was more important than how its visuals.

[@CuriosityShow]

Yes, we always tried to show children how to make and do things with old stuff around the house - Rob

[@Randsurfer]

That was my first thought, half the video is showing how to make the drawing gizmo. Would have been great if the presenter brought his nephew in to hold the table steady.

[@Randsurfer]

@@mvrdamonxy7942 Well that's unfortunate.

[@davidgray2845]

Randsurfer 😂

[@i-deni-i5138]

You do know that visuals are important and count as content?

[@agingerbeard]

What a treasure this show is. We need a modern equivalent, would love to see more of these hosts they make everything simple and enjoyable thanks so much 🙏

[@coxfuture]

we have it, it's called vsauce. he even did this same demonstration

[@agingerbeard]

@@coxfuture not a fan, his mannerisms are so fake, like he's playing a character. These guys are just giving information not trying hard to be "wacky and interesting".

[@rgw5991]

@@agingerbeard yeah i agree. This was back when life was simpler. Everyon is trying to be so "Extra" that it blows you away. Theres no space to "Take it in" anymore.

[@paulclissold1525]

Do you remember when sesame street used to teach. Its scary now.

[@joelmalone]

Steve Mould’s channel is full of stuff like this, plus the occasional Dad Joke.

[@vaels5682]

For anyone who wants to go deeper on this - look into the brachistocrone and how it was developed in relation to refraction. And if you still desire more, the rabbit hole goes on with the principle of least action.

[@g0d5m15t4k3]

Thank you, Satan, I will indeed look into these... :)

[@DMZRPG]

Thx guy. Checking it out now

[@kevindantas7171]

I'll show you least actio...

[@TwoLeggedTriceratops]

I heard of that dinosaur before

[@davehobwest]

The brachistocrone problem goes to the calculus of variation via Lagrange and Euler, with an anonymous cameo from the lion himself, Newton. A deep rabbit hole indeed.

[@ByronTexas]

That was pretty awesome. No frills, basic tools. Complexity turned into simplicity

[@noname54eeee]

Yeah that was the cool thing about this show they wanted to make sure that anything they did on the show kids could replicate at home using household objects themselves

[@glenncalzada1707]

And therein is the genius of the program.

[@reviandelumiel2833]

And simplicity turned into complexity

[@glenncalzada1707]

@Thegame .Dev sometimes actions speak louder than words.

[@kneeman66]

I love engineering principles. I once asked an engineer on how he knows how strong to build a building and he said that he has all these equations and formulas and after he figures it out he just multiplies his final calculation x3.

[@grantm6514]

Our structures lecturer in architecture school showed us how to calculate the size required for a timber floor joist, and then said "but the carpenter will struggle to hit that with a nail, so better double the thickness".

[@benmurtagh4537]

Reminds me of the old saying: “Anyone can build a bridge, but only an engineer can build a bridge that just about stands.”

[@NYCZ31]

This seems pretty common even in today’s era of computers. John Roebling, who designed the Brooklyn Bridge, did all the math and then multiplied it by 6 to make sure everything was strong enough. This turned out to be prescient because a manufacturing flaw in the suspension cables meant they weren’t as strong as designed, but Roebling found that even with the flawed cables everything would be four times the strength needed, which was still considered sufficient. 138 years later the bridge still stands proudly.

[@Mikowmer]

@@NYCZ31 Yep. Safety Factor. Protects against damage and manufacturing faults. Very useful.

[@littlecabininthebigwoods5720]

It’s simple. The materials were tested until they broke and given a value. If something is designed to withstand only it’s max, it would break. It’s like we find out what the maximum weight you can lift is and then tell you to hold it all day. You better get three times as strong or use a weight that’s 3 times less if you don’t want it to slip from your hands.

[@thegroundpros]

The way you can cram so much knowledge into such a short period of time is amazing.

[@peterschaeffer]

An isochronous curve is, in fact, the correct curve for a time-keeping pendulum. It is however, impossible to use (for pendulums) in practice. Sir Isaac Newton (along with Leibniz) was challenged to solve two mathematical problems by Johann Bernoulli. Newton solved both problems in a short period of time. One of them was the derivation of the isochronous curve. After Newton submitted his solutions anonymously. Bernoulli recognized the anonymous winner in public with the phrase, “tanquam ex ungue leonem,” Latin for “we know the lion by his claw.”

[@00gsean]

Peter Schaeffer respectfully I am an amateur student of the historical lives of scientist. Could you please cite the publication you acquired this footnote? As a young man I hated history more than anything, likely due to my professors and the states approved text books, but as I've grown older my appreciation for scientific history and pre western history has improved vastly. If all of history could be taught along side and through scientific advances of the day my interest would have been markedly different. Thank You in advance.

[@peterschaeffer]

@@00gsean Of course, I would be glad to. You can find several sources for the quote. Start with "Later life of Isaac Newton" in Wikipedia. You can also take a look at "Brachistochrone curve" (also in Wikipedia) and "The brachistochrone problem", www.math.purdue.edu/~eremenko/bernoulli.html, etc. There are several interesting aspects to this. Newton's talent was immense. However, the Calculus he devised was actually not as good as the Calculus invented by Leibniz. As long as Newton lived, this was not apparent because of the immense talent of Newton. After Newton died, the Mathematics community shifted to the Calculus system devised by Leibniz (which is what we use today).

[@musamor75]

Thank you for this tidbit. Popular culture can be scintillating at times.

[@peterschaeffer]

My comments above contain a partial error. My comments are about isochronous curves (also called tautochrone curves). These are equal time curves, but impossible to use with real pendulums. Newton derived brachistochrone curves, not tautochrone curves. Christiaan Huygens derived the correct formula for tautochronous curves. It turns out tautochrone curves are the same as brachistochrone curves. Note that Galileo thought that semicircles were tautochronous curves. He believed that the period of a pendulum was independent of its amplitude. This turns out to be very close to true, but not quite true. Pendulums can be used for clocks, even though semicircles are not tautochronous curves.

[@bbbildhuu]

Bernoulli as in the Bernoulli principle?

[@SloopADoopy]

The first new thing I’ve learned in 2019

[@CuriosityShow]

Kepp watching and there will be many more - Happy New year - Rob

[@Belkan2087]

Same.

[@jpaxx5932]

James S just thought the same!

[@victorserrano7939]

Thts was actually interesting

[@stivi739]

I learnt how to fix my airon on my astra

[@Guzman88A]

KZbin thinks I’m not watching enough educational videos. Thanks for caring.

[@YahYou813]

Exactly, sometimes too much trash watching

[@waterbourne9282]

Cool. Great presentation. No fluff and flash, just pleasant conveyance of interesting information. Thanks.

[@Yewbzee]

This was one of those totally random links in my “recommended” list. I’m glad I watched it. Very interesting. Thanks.

[@HiVizCamo]

I've had it turn up twice in about 6 months.

[@nabsludwig7462]

The curvature is continuously varying along the path, thus creating unique acceleration characteristics from every starting point along the curve. The nearer to the finish point you start, the less the acceleration.

[@kez850]

Yes this wasn’t really surprising at all. The fact that people employ this into technology is kind mind blowing though.

[@SunshineSuperstar]

@@kez850 what's truly mind blowing, with the fact in question being true, is that the curve won against the straight line. I wonder how it would fare against the vertical drop?

[@jeffbeck9444]

Hi, would this make for a strong archway? I built a arbor to enter our garden, the curve I finally went with was curiously similar. I wish I knew how to construct that curve then. It would have saved alot of experimenting. Nature is so smart, and so are you people that can extract these things from it. Seems simple but it's ingenious. Thanks J in Denver

[@SimonO1919]

Things like this are some of the most fascinating things in this world. How come it's like this? What would it do if we weren't here to realise it? Now that we realised it, what can we do with it? (and so on...) Truly amazing stuff!

[@DeadlyVerge]

Like the Coanda effect, Laminar flow, etc... Could we create advanced technology using these natural laws of physics?

[@Superabound2]

@@DeadlyVerge we already do

[@xxnocturnaltank859]

Yeah, I feel like some people don't grasp how phenomenal and fascinating some of concepts in physics and nature are. Everything I connected some way, and there has to be so many more things we've yet to discover

[@vvey4523]

I don't get how this one is fascinating Especially the part where the curve ball goes faster than the straight one. It was so obviously going to happen that for a moment I thought "wait, it won't ?", but it turns out the curve ball does go faster thanks to the drop So... everything's normal

[@SimonO1919]

​@@vvey4523 It wasn't that obvious, because the straight line is also steep and is much less distance than the curve, even though the curve has a bigger drop, it needs to travel more. You don't find this fascinating, because you probably think this is how all curves work, or maybe you don't care about how curves work, or why they work that way. Get it now? You don't get why it's fascinating because you don't get it, aren't interested in it, etc. Hope this helps.

[@BassMatt1972]

Saw this as a kid on TV.. Still love it.. Im 51 now haha.. One of my fave shows as a kid..

[@credo3106]

Thanks for this explanation and demonstration. This might explain why when I start skateboarding at the bottom of a ramp, I always collide at the centre point with someone who starts at the top. I'm going to use this principle in my 3D simulations for creating some cool effects.

[@CuriosityShow]

A pleasure - lots more at kzbin.info with new stuff each week for subscribers - Rob

[@MrOod67]

did you manage to create some cool effects in the end?

[@MrGermandeutsch]

@@MrOod67 good question

[@zachramon1602]

@@MrOod67 I would also like to see said effects

[@MrDot-hw5wb]

@@zachramon1602 same

[@andersmartinson1750]

An absolute delight. Brilliantly presented and executed. I love the use of simple materials to demonstrate the concept.

[@CuriosityShow]

Many thanks - lots more on kzbin.info with new stuff each week for subscribers - Rob

[@darrenrobinson9041]

TV executive today: Wait - did he say "tobacco tin" on a kids show ? Cancel it immediately.

[@arunkennedy9267]

The thing that baffles me the most is that modern KZbin videos would do the same thing with a bisare amount of tech and unnecessary stuff, this video is soo elegant no matter how many times I see it.

[@SpatialGuy77]

I’m 51 and I used to watch this show when I was a young boy - no doubt one of the reasons I became a scientist!!AWESOME🤓

[@CuriosityShow]

Good on you. have you subscribed at kzbin.info - Rob

[@jasonsttarkus]

Curiosity Show was my favourite after school show back in the early 80s - thanks Rob & Deane!

[@paulstovall3777]

For some years now, I've been working on a closed system using a three dimensional brachistochronic curves in the form of convergent vertices, hydro/mechanical device with one moving part that may actually show potential promise for the breaking of or at least the side stepping around Newtonian theorem. Put more succinctly, I'm diligently looking for logical reasons as to why this system (not my original concept, tho some redesigning has been required) 'wouldn't work' and have yet to be able to find one. Outside of the simple fact that 'Newton' said it can't be done. Granted, he like Einstein among many others were brilliant given what they had available and knew in their respective times. But, then again (like the Wright Bros), I've always been one to questing just about everything I encounter if it was reasonable to do so. To include Newton. I detest being told that 'I can't'. I would really enjoy the input of an engineer (preferably one diligent with hydro/mechanical background) who can speak 'math' and who is willing to think a bit 'outside the box'. I have Asperger Syndrome, a capacity for eidetic imagery but which, for whatever reason, leaves me mathematically challenged. Perhaps someone of this ilk could answer the question of potential feasibility.

[@darkseid856]

Sir, I also want to be a scientist(theoretical physicist to be precise) . Sir, may you give some useful information or tips for me? 😀

[@hectormzqt6169]

@@darkseid856 Believe in God and all else will come naturally.

[@caseytodd7632]

I wonder how much this man would charge to come to someone's house and read bed time stories to them every night. Asking for a 31-year old friend........

[@CuriosityShow]

If they live in Adelaide, not a great deal - if the story is good - Rob

[@lolindirlink]

What do you mean? youtube is free to take with you wherever you want ;)

[@buckrowley1506]

casey , I did not know there were isochronous bed time stories , you learn something every time you watch youtube !

[@xflynskywlkr27]

Me first lol

[@marztar]

@@buckrowley1506 i've got isochronous testicles no matter what girl i take to bed.. fat, thin, white, asian.. my nuts bust after the same amount of pumps.

[@TheSleeplessSleeperAgent]

I love this, every part of this brought me along at an easygoing pace, one that didn't make my brain feel like it was being jellied; made it easy to understand; and was calmly explained in a manner that made me think of Bob Ross. Lovely experience.

[@CrazyMrTim]

Bob Ross was a legend!

[@TheSleeplessSleeperAgent]

@@CrazyMrTim was? Still is!

[@chiefstain]

@@TheSleeplessSleeperAgent They could have fallen out, you never know !

[@CyberneticArgumentCreator]

Sucks that there isn't a single piece of television made today catered to learning.

[@chiefstain]

@@CyberneticArgumentCreator I think there is, well the equivalent. Tv is dieing out. People watch things online now. On KZbin there's lots of channels educating the masses

[@LukaszBrodziak]

That is why I love the old science tv shows. In Poland we used have a lot of these in National TV back in the day. Easy DIY experiments that made physics and science in generał easy to digest and understand. I do miss these.

[@riloh58]

My goodness. I remember this show when I was (much) younger. Excellent television. I watched it religiously. Thank you to all involved in producing it and it is still great today.

[@styxcreek]

I grew up watching these guys but I was a thick ignorant child. Much more enjoyable as a 53 year old.

[@guneetify]

What year was this episode from?

[@ItsWuLx]

Im 18

[@darylg.4270]

Why does it seem the older we get the smarter/wiser we seem to be!! I hate the fact that I was a good way back when but now I know I could have been so much better and could go back and fix things, ugh.. lol!!!

[@cachi-7878]

Now you’re a thick ignorant 53 year old? 🤪

[@chrisvstar]

@@cachi-7878 Haha! I feel the same as Nathan! This show is actually more fascinating for me as an adult than watching it in the 80's as a kid. Especially after studying science since then; Now I see so much more of it going on in these sketches. I particularly like how carefully and meticulously explained the procedures of everything in these presentations are. A very important (p)art of science.

[@caseytodd7632]

Now I know how Thanos felt. I now too, am cursed with knowledge.

[@TheMusicalFruit]

The isochronous curve is perfectly balanced, as all things should be.

[@OneFastRaccoon]

I love this. I love all of this.

[@CuriosityShow]

Thanks. Curiosity Show was a national science program for children featuring Dr Rob Morrison and Dr Deane Hutton. It was made in Adelaide, South Australia and screened nationally in Australia as well as in Europe, Asia and Australasia (14 countries) from 1972-1990. Deane and Rob intentionally used everyday items around the house (like old cans) so that children could repeat the demonstrations with materials they had to hand. In 1984 Curiosity Show won the Prix Jeunesse International, the world's top award for children's TV programs. Rob and Deane are steadily uploading segments at kzbin.info Why not subscribe?

[@frankburdodrums8984]

Casey Todd 🤔😁

[@TheSign2020]

You mean you're curved with knowledge

[@warpspeednow]

Loved that show back in the 70's, can still remember the theme music as well.

[@oo0Spyder0oo]

Back when Aus had some of the best educational tv ever, along with Julius sumner miller and wonder world etc. This was the dog's bollocks, always hooked you in and their enthusiasm and straight talking made you a part of the show.

[@CuriosityShow]

Many thanks - lots more at kzbin.info Please spread the word - Rob

[@oo0Spyder0oo]

Amazing, I thought this was a fan based collection until I just googled that you guys have the rights to the old episodes and this is in fact a youtube channel run by the legends themselves. Pioneers of tv, among the likes of the Leyland bros etc. That's fantastic. Just made my youtube viewing all the better for it. Thank you.

[@jk9554]

I've looked for this for ages... I remember watching this almost thirty years ago (when we only received four TV channels, and one of them had the german syndication of the show). Thanks Rob and Deane, I've learned a lot from the show as a kid and I'm glad that you were able to bring it back, so I can finally re-watch all those bits that entertained me as a child.

[@classydays43]

Russel Coight was an exceptional educationalist. Certainly a bar of intellect above the rest.

[@oo0Spyder0oo]

@@classydays43 haha yes. We played that series over and over taking the kids to their school camp. Great fun.

[@gregmckeeswildthings9647]

Have to thank you two Rob and Deane for the brilliant and continuing efforts at science and reason education over the years and your excellent use of familiar everyday items to illustrate principles of physics. Its still needed now more than ever. I watched you as a school kid and as an almost retired design engineer still enjoy watching. You guys are legends

[@CuriosityShow]

Very kind - yes. we tried to use everyday materials as much as we could - glad you picked it - Rob

[@gregmckeeswildthings9647]

@@CuriosityShow Wonderful Rob. I marvel at the legacy you guys have created, inspiring and influencing so many Australian innovators and scientists and artists. My uni classmates remember and were inspired by your show and recalled it at a recent reunion. Personally I loved your accessible found aesthetic and with Heath Robinson influence adopted it in comical exhibition work in the 80s. kzbin.info/www/bejne/oqSrlKd5hdKZr7s So glad you have made your show available on youtube to inspire new generations ! Well done gents!

[@MrStredders]

+1 confirm. I was only telling my kids the other day about watching The Curiosity Show after school as a kid. So glad this content is here :D

[@LtPowers]

Everyday items like... tobacco tins! Times have changed!

[@xiongpaolee]

Geometry meets gravity. This principle applies to whatever "slingshot" effects might naturally occur in the traveling of objects. Best popular example is the half pipe in sports, notice it's not actually a half circle, it's a isochronus curve. This helps give the athletes the extra speed to make those cool jumps.

[@transatlant1c]

I’d never noticed that before but in retrospect, so obvious. Thanks!

[@peedee4065]

3:24 shows the side view of the isochronus curve. I can assure you that is not a curve I've ever seen in any skatepark (I've been skating in parks actively since 2011). Keep in mind that the isochronus curve is a semicircle (1/2 of a circle), meaning that you can't take parts of it and stick straight sections in it, that would by definition make it not an isochronus curve. The nature of skateparks doesn't necessarily rely on any particular curve, people debate the science of "pumping" in skateparks and say it's not simply a matter of conservation of angular momentum (but to me that makes sense, simply), bottom line is that you simply need some smooth radii that have some element of vertical change. And in skateparks you'll find variations in radii that make some parks better for certain disciplines: large radii suit bmx'ers while shorter radii suit skateboarders.

[@imbaby5499]

Gravity IS geometry (of spacetime).

[@SirTylerGolf]

​@@peedee4065the isochronic curve is not a semi circle, that's even covered in this video

[@peedee4065]

@@SirTylerGolf O.k. thank you, I'm not sure what I was getting at when I used "semi-circle." My point is that the isochronus curve is set and distinct in its shape, the ONLY variation in the shape of isochronus curves would be due to the diameter of the wheel generating them, and if you think about it ALL isochronus curves are identical in shape, they just vary in size. I make this point because again I've never seen such a curve in a skatepark.

[@X-Gen-001]

Oh man, flashbacks of sitting crossed legged on 1970's school carpeting watching these guys on the old crt. They presented of course far more interesting concepts than anything our teacher had to say which was usually along the lines of shut up or I'll beat you with a stick. Ah memories, yeah we prefered the tv. Some people thought we watched too much back then, I don't know what they were worried about. I watched tv when I was a kid and I turned out tv.

[@CuriosityShow]

Back then, there had to be a required number of hours of certified 'C' standard shown by commercial TV each week. All gone now - Rob

[@socksumi]

Useful for gaining maximum speed when constructing roller coasters.

[@bhaskar08]

This curve takes the shortest time. Does not guarantee you the maximum speed.

[@Rick-the-Swift]

If you reversed the curve it would take much longer for the coaster to descend but it's speed at the very end would be greater than it would at any point if it were traveling on the inverse side.

[@Keneo1]

Maximum speed is just straight down

[@rienkvandenberg]

Maximum speed is only related to the difference in height from start to end point. Without friction and drag ofcourse

[@user-gr4hb2yn3x]

it's just like vsauce! but without hipster music...

[@not_my_name5200]

so it's exactly like vsauce then?

[@DrumRoody]

Or the soy

[@rocknral]

Thankyou Rob for uploading. Your show was a weekly highlight of my childhood. Brings back so many memories seeing this. Great stuff.

[@CuriosityShow]

Thanks very much, most appreciated - Rob

[@richardwhitehead6966]

Recommended by KZbin, not sure why (probably because I was watching Mark Rober). Damn, I loved this show growing up. Give people an enjoyable and understandable explanation for anything (but don't patronise their intelligence) and you will be surprised what they can learn and retain.

[@horsepower523]

Can I just say how much I enjoyed this. I enjoyed it immensely, that's how much. A lot more than I expected. Isochronous curve has made my day. Never thought I'd say that sentence in my life lol. Sometimes you find a real gem on KZbin which leaves a lasting impression. This video is definitely one of those gems in my book.

[@CuriosityShow]

Glad you enjoyed it. Subscribe at kzbin.info for more segments each week - Rob

[@arconeagain]

The only way to improve it is if he were wearing one of his jumpers.

[@sf1292]

It didn't even occur in my mind to stop for a second lol

[@dennisonida5104]

@@CuriosityShow 1985

[@maxedison8259]

An excellent demonstration and explanation of an Engineering principle! This was the type of programme you would see, early on Sunday mornings, or late at night, via the 'Open University'. I never understood much about mathematics, but I really enjoyed the programmes dedicated to Science and Physics.

[@DankMatter]

Anyone else get this in their recommended?

[@ezekielarmstrong9905]

Dank Matter yes lol

[@joebodynobody764]

It's not like I spend my time looking this shit up. I might have to start though.

[@mikegniadek3396]

Howed you gey between 2 people who posted a day ago? But yes i did

[@noahjames9457]

No. No one else.

[@brians2170]

yeah, but at least I learned something

[@SamuL147]

No matter the subject, but hearing ppl talk about stuff with this sort of passion is just mesmerizing

[@grahamallen934]

This isochronus curve is used in the half pipe used in snowboard 🏂 and skateboarding jumps.. Using the effects of Gravity... Momentum.. Speed.. And distance travelled to perform breathtaking Aerial Jumps...

[@garryiglesias4074]

Finally an educated guy who doesn't whine "nobody use it" or such stupidities... :)

[@billd9057]

Good point 👍

[@garyindiana2127]

Actually nah, there's something called flatbottom that any decent ramp or halfpipe has and is really necessary to give the rider some neutral time to relax their legs before approaching the oncoming wall.

[@666zombee]

@@garyindiana2127 flatbottom is not a true "halfpipe"

[@garyindiana2127]

@@666zombee maybe you'd be surprised to know that skaters have their own slang, also all pipes aren't round

[@davidlanham99]

I have been telling people this for years and no one will listen.

[@JOJOKYRA]

I can only start to imagine the numerous applicability....

[@stephenreos9316]

Thank you for dying for our sins

[@grahamdavies8924]

My cat discovered it on his own.

[@gantmj]

Ha

[@BikingVikingHH]

Now that’s a funny comment

[@RobsWorld]

Very cool presentation. I guess it has to do with the angle getting exponentially closer to 90 degrees as it goes towards the edge and this therefore causes an increase in speed or decrease in release speed as it moves along the curve. I’m sure there is some physics equation to explain this but I think my brain had enough for now 🙂👍🏻

[@ravencstwo]

VSauce and the myth busters dude did a video on this. it's called the brachistocrone

[@toddly1133]

@@ravencstwo that sounds like the name of a dinosaur to me. Lol! 🦕 🦖 Or perhaps it would be the name of a new medicine. 💊 💉 Lol!

[@anthony9656]

The curve was found by Newton and some of his contemporaries long ago. The formal way it is found nowadays is via the Euler-Lagrange equation (calculus of variations). If you learned calculus Paul Nahin's book When Least is Best gets into all the details, worth checking out!

[@michelfouche4599]

Actually that would be a tautochrone curve. They are related, but not technically the same.

[@anthony9656]

@@michelfouche4599 Yes in the presentation he called it a isochrone curve, which in fact has the same meaning as tautochrone curve. From the Greek, brachisto=fastest, iso=equal, tauto=same, and chrone=time. The brachistochrone is the fastest curve from the cusp to any other point on the upsidedown cycloid-- it has to include the cusp. The tautochrone on the other hand is any section of the upsidedown cycloid-- but it has to include the lowest point of the cycloid, where the steel bearings arrive at the same time, regardless of where they start from above on the curve.

[@allenplant1702]

Amazing that this man actually got paid to do things like this! Shows like this should exist currently.

[@Gryflir]

idk why youtube recommends me that but it brings me back good memories.

[@bobayersquebec]

if you want to save more time use: IDKY...

[@01rai01]

A curve thats part of a circle, has an equal curvature ( or slope ) at all its points, where as the isochronous curve does not. It is almost vertical at the sides and flattens out gradually top & bottom. The speed at which the ball moves at different positions on the curve is related to the slope at that point and how potential and kinetic energy of the ball changes. Since the ball is released with zero kinetic energy, all of its motion relies on the potential energy of the ball, trajected along the slope of the curve. You'll find there will always be a give and take (trade-off) between the height and the distance away from center, thats relates to how fast the ball moves when released.

[@carmelpule6954]

In my younger days as a Dockyard apprentice in Malta and in Chatham, at the Dockyard school we used to call this this a cycloid and there is the epicycloid and the hypocycloid associated with it. I believe gears are generated from this curve. The " isochronous " title came about because of its " time" functions when it carries an object on its hollow curve where the time of descent is not dependent on the starting point. A cycloid is the curve traced by a point on the rim of a circular wheel as the wheel rolls along a straight line without slipping. A cycloid is a specific form of trochoid and is an example of a roulette, a curve generated by a curve rolling on another curve. The cycloid, with the cusps pointing upward, is the curve of fastest descent under constant gravity, and is also the form of a curve for which the period of an object in descent on the curve does not depend on the object's starting position.

[@anthonyperry5227]

Very true! Often part of engineering geometric exam questions. The majority of gear teeth are formed using cycloidal geometry. Larger gear teeth are often formed from a involute curve.

[@Kenzofeis]

@@anthonyperry5227 Popularly known as hypoid gears

[@xdeadwrongxdeadwrong7181]

Ohhhh...So that's how David took Goliath down.

[@Kenzofeis]

@@xdeadwrongxdeadwrong7181 No but I think it has something to do with Odyssevs

[@carmelpule6954]

Do note that many people do not know that on a car driving at any speed even a high speed, the one point on the curve of the rotating wheel touching the ground is absolutely stationary as long as there is no slipping as when driving on ice. The highest point on the wheel is traveling instantaneously at twice the speed of the car, while the only part of the wheel that is traveling at the same speed as the car is the central shaft of the wheel.

[@mickdecarteret6000]

I love stumbling on things by accident and this is fantastic. Both relaxing (because of the voice and chilled out manner of delivery) and fascinating and informative. The chap reminded me of Brian Cant a bit.

[@alj644]

Bob Ross brother...

[@billant2]

It's actually Rob Ross himself without the afro... "itsy-bitsy balls rolling around... there!!" tsk-tsk

[@Rollerbear712]

British Ross?

[@stockfootage8096]

He’s clearly Australian, not british.

[@Spyro_2076]

happy little curve..

[@justaway_of_the_samurai]

You can notice that although the balls will reach that center mark at the same time, the one that started at the lower point on the curve bounces farther back when it collides with the other ball. This implies a few things: 1. The ball starting at the lower point had a lower amount of momentum than the other. 2. That ball had the same mass as the other ball, so the difference in momentum was because it was moving at a lower speed by the point it reached the center. 3. Since the balls started at different heights, they naturally also started with different amounts of potential energy and the same amount of kinetic energy, which was 0. So, this would naturally explain the difference in momentum and velocity when the 2 balls meet, which confirms the law of conservation of energy was upheld without any unknown forces adding energy into the system. The fact that the balls reach the center at the same time is actually the result of the inconsistent centripetal acceleration caused by this particular curve. The top of the curve is essentially a flat drop, so the only force on the ball at that point is gravity. Lower on the curve though, the ball fallows the curve at an angle, so its vertical velocity is converted bit by bit to horizontal velocity, until it reaches the center point. Although the conversion of the vertical speed to horizontal speed gives it a higher resulting velocity when it reaches the center, it had to travel a greater distance around the curve to get there than a ball starting at a lower point. This curve is special, because it perfectly balances the trade-off ratio between achieving greater end velocities at the cost of increasing the total distance traveled by the balls, so that the total distance traveled, divided by the average velocity throughout the curve, is equal to a constant amount of time elapsed. Or * D / V' = C *

[@synchronium24]

Bravo! One remaining question. When comparing a ball traveling on an isochronous curve to traveling along a straight line, the former is faster. I get that the ball gains more momentum along the isochronous curve, but it also travels less distance. Do you have any kind of intuitive explanation for why momentum wins out in this case?

[@hzhnx_0]

Or maybe something more simple, like human error not releasing the balls at the exact same time

[@kelvin1316]

Thats a long way to say "Magic" LOL 😉😇

[@productwholeslave2122]

Obviously i haven't done this experiment; hence my question: would the two balls (hah! Balls) meet at the Centerpoint if one was released at the very top of the one side, and the other released like one diameter away from the Centerpoint?

[@MrFearless]

Very informative and well explained. I'm glad its found a home here on KZbin for so many to enjoy.

[@CuriosityShow]

Many thanks. If you haven't alreday subscribed you can do it at kzbin.info and get new segments each week - Rob

[@castleanthrax1833]

This was one of my favorite TV shows when I was a kid. Brilliant Australian television. ✌️🇦🇺

[@CuriosityShow]

Many thanks - Rob

[@JakonDeluxe]

Bob Ross Tim (from Grand Illusions) Rob The trinity of tranquillity.

[@BadWebDiver]

So true!

[@sbaxter4207]

grand illusions is in a thumbnail link over there for me, lol>>

[@Observ45er]

Thanks for the reminder about him.

[@matttillman7430]

I'm 57, this is the first time I've ever heard of an isochronous curve. This video is fascinating!

[@CuriosityShow]

Many thanks. Why not subscribe at kzbin.info for hundreds more segments - Rob

[@edwardtupper6374]

So you wagged most of 4th form too huh

[@michaelwoehrl1746]

So the fastest distance between two points is an isochronic curve!

[@Elephantstonica]

Michael Woehrl When descending. Someone should tell the various birds of prey.

[@DorinMunteanu]

@@Elephantstonica they may know it already

[@LordButterstotch]

Only when there is a gravitational force applied, the straight line has more resistance to gravity but the curve allows for "freefall" thus the ball on the curve has more acceleration and the ball on the line has more inertia. This is why a vert ramp (half pipe) for skateboarding is the shape it is.

[@Elephantstonica]

Daniel Beaird Isn’t that what I said? Sans the superfluous pretension.

[@michaelwoehrl1746]

Far out Walter.

[@tysonhartle2439]

We went through this demonstration/lesson in Physics in High School. It was one of those lessons that I will always remember as our teacher also explained how, based on that curve and how it graphs out over multiple revolutions and how it relates to distance and speed, there is a point where the part of the tire touching the ground is not going anywhere, yet your vehicle is moving forward. This lesson and lessons on infinity.... those were some of my favorites. My teacher took the point on a ruler and asked us to divide that by 2, then that by 2, then that by 2, etc. We obviously kept getting smaller and smaller numbers but soon realized that no matter how many times you divide the space on a ruler between 1" and 0 that you will never get to 0. You could divide the number in half for the rest of your life and never get to 0. So does that mean that there is an infinite amount of space between all objects, all matter?

[@MrDonteallen]

Can u Explain that ruler example again whenever u get a chance i think i get it bt dnt lol

[@iclimbeverything2990]

@@MrDonteallen what he's saying is that you can divide 1 infinitely and never get 0. Because decimals are infinite. For example 1/2, all the way to 1/8192, all the way to 1/2,147,483,648 if you do that math you will not get 0. Calculators might get 0 but that's because they don't show all the decimals. It would be like 0.000000000000000000000000123 whatever

[@MrDonteallen]

@@iclimbeverything2990 Thank you brother for taking your time out and expounding on this matter i greatly appreciate it!

[@MrDonteallen]

@@iclimbeverything2990 let me ask you this question then, are you saying our calculators technically shud start at 1 instead of 0?

[@RiskyDramaUploads]

Zeno's paradoxes of motion: the dichotomy paradox, and Achilles and the tortoise

[@Thisonegoestoeleven666]

Used to love Rob and Deane. Helped make me the scientist I am today. Brilliant educators.

[@ZakeBudek]

Remember kids, smoke all your pipe tobacco first.

[@petersharp90]

And then use your matches to set fire to stuff afterwards.

[@drowningin]

I SMOKE CRACK!

[@PrinceWesterburg]

Glad he used a nice new tin as it was going out on TV

[@drowningin]

@42 -42 nuh uh I said I SMOKE CRACK we all do. Us kids

[@robert__]

@@drowningin me too

[@govshill4557]

Ah, I remember when television used to make you smarter, not dumber. Now we get The Bachelor.

[@TomWDW1]

Except that this is one example of a show from the 80s and you are using one example of a show from today. We still have some smart shows (and many more on KZbin). And the 80s had some real horseshit (Joanie Loves Chachi, anyone?). Stop looking at life through a nostalgia lens, it's boring and overdone.

[@QuietDuplicity]

Genuine question since I haven't owned a television in over 15 years, I hate the thing and even try to avoid going to peoples homes if they have a habit of having the thing on as background noise. What are some examples of "smart shows" on television today and do they present in such a way as this where they don't talk down to their audience?

[@anodosarcade7355]

When was this mythical time?

[@bruhgart]

Or honey boo boo on The Learning Channel.

[@sereanaduwai8313]

hahahahahaha! They all ran out of ideas!

[@seandonahue8464]

It never ceases to amazing me the knowledge out there that it would never have occurred to me to seek. I don’t know if I would have know the earth was round if I’d not grown up when it was a commonly known. Sadly, it may never have occurred to me to ask, embarrassing as that is. You guys are amazing!

[@danpapworth6430]

Love this kind of tabletop presentation. Properly interesting because the subject is interesting and the presenter draws attention away from himself to the phenomenon being considered.

[@Mr518888]

This is like vsauce before it existed

[@spankeyfish]

Kids' tv in the 80s and 90s was like this too,

[@Mr518888]

I used to watch Bill Nye as a kid, and it has a similar feel to it, maybe a faster pace though.

[@skilletpan5674]

This _was_ kids T.V. in the 80's and 90's. All that's missing is the awsome intro and outro of the full tv show.

[@PandA_show]

Awesome

[@commentresurrection1841]

skillet pan- nope...all that's missing is the awesome intro and outro of the full tv show. AND awesome 80's and 90's commercials

[@EkardRimidalv]

"The road to success isn't a straight line, it's an isochronus curve" -Sun Tzu, The Art Of Road or Success idk you decide

[@IRONHEAD12701]

This gentleman reminds me of my physics professor. Educational, but not monotone. Entertaining, but not joking around. His explanation is in the “Goldilocks zone”❤ Well said in Lehmans terms. Not like a 300 i.q. genius

[@sleepingbanshee_]

_Lets puts some happy trees on that curve._

[@crystalm4324]

Youngblood - don’t forget a little bush and perhaps a little bubbling brook off in the distance, then just tap a few happy clouds watching over.

[@sleepingbanshee_]

@@crystalm4324 _there, that looks about right._

[@recovery116]

"Go on, beat the devil outta that brush."

[@atypical_moto]

Use your little dooder there with some water.

[@sparkyhart6666]

Bob love to smoke those happy little Bushes 🧔lol

[@biggutter3335]

I'm going to use this to get my employees to show up to work at the same time. Brilliant!

[@ryanwilson5936]

Severely underrated comment right there.

[@yardswithstripesinc1042]

But they would still have to leave on time :)

[@paulmuaddib1764]

I have officially reached the end of the internet...signing off

[@mftripz8445]

Yeet your journey has just begun. Watch a video called "Me! Me! Me!" Its fucking cringy but endure it

[@moefritz6225]

Paul Muad'dib ahahaha... Ya, I'm alone at night in the bathroom watching this thinking uhhhhh!?!?!?!?!?

[@19dines77]

lol. but she had the Isochronous curve behind.

[@zzzhuh]

*Flying High!! On the wings of my dreams!*

[@SeanFerree]

Same 😁😁

[@garrybaldy327]

It's gravity. A steeper slope creates the stronger gravitational pull, hence why the steep curve beats the not-so-steep straight line. I'm sure it's slightly more complicated than that, but that's the nuts and bolts of it.

[@AV036]

I'll bet you think gravity is the best chit🤗 You're probably happily clinging to that tiny anti-centrifugal spinning water ball invented by NASA, where there's an atmosphere of 14psi right next to an open big magical push pull sky vacuum. 🤭 It's very simple neither slope created anything. (YOU) fall through the air @ X vs float or sink in water @ Y 👇flap?🤪

[@Gallardo6669]

You guys influenced my youth so great!!! Thank you for ever...

[@SVTJD]

KZbin knows me better than my wife

[@JohnnyBourassa]

Latnlvr - not sure what wormhole was created to bring forward this gem from the past - but oh boy, your comment left me in tears 😂

[@instantdislikechannel5699]

You should get divorced I guess

[@AJman14]

That's because you spend more time on KZbin than with your wife.

[@roba6216]

If your wife new you as well as KZbin she'd ask for a divorce

[@daveplumley7854]

All of these are brilliant responses. I like it here...

[@MikeKobb]

Great demo, really cool! This made me think of my old Spirograph. I’m sure there was a way to draw an isochronous curve with that setup.

[@ferngrows6740]

Mike - I was thinking the same thing.

[@fishirium3971]

whats thee difference between this and a brachistachrone

[@harrymills2770]

You'd have to stick the pencil tip in the gear along the edge, rather than one of the holes in one of those disks, but yes. But you could probably do it free-hand, without tape. Just one of the disks, one straight edge (comes with Spirograph), cardboard, paper, and push pins to anchor the straight edge. Pretty much all a part of spirograph, only I don't think using a pen along the outer edge is in any of their instructions.

[@castleanthrax1833]

@@harrymills2770 Why would you need to put the pencil on the edge. Surely the same thing would happen if you put the pencil anywhere in the far outside holes?

[@matonatomic]

ha..ha...ha... Yes, coz I don't think anyone has a spare 'tobacco tin' sitting around :)

[@MarcinHopa8]

Ahhh this old educational vids have such a unique vibe to them. So juicy, ripe, rich in knowledge and calming

[@lifes2short]

Anyone else a little high and said "F it, let's see where this goes." And are now happier because you stayed? No? Okay. Just me then 😂

[@737driver]

Very interesting. Also, if you put the speed at 0.5, the guy sounds like a drunk mad man.

[@PeanutVendor69]

Haha so legit

[@dylanwest2308]

Haha drunken old man trying to explain something at the pub 100%

[@sheymartin2107]

What a guy. Your a fucking genius, how did you even find this out?!

[@elementsofphysicalreality]

Shey Martin he probably slowed it down to see the balls hit.

[@sheymartin2107]

@@elementsofphysicalreality oh lol

[@njt002]

Before discovering this, it was slow-going in the roller coaster business.

[@victorl225]

I don’t know what got pushed out of my brain after learning this but it was worth it.

[@hashtag415]

I'll consider this my learning curve.

[@SH19922x]

If you're learning curve was that efficient you would be on mars and not youtube lol.

[@seanevertts9096]

Funny

[@HazeAnderson]

brilliant 😂

[@baybora95]

@@SH19922x well neither is yours since you cant differentiate your from you're

[@bern1e74]

How the hell did someone find this out???

[@AsmodeusMictian]

By exploring the world around them and wondering how it works and why it works that way. Then apply scientific method. Beautiful when you think about it, there's nothing stopping any of us from doing these things except the will and the time.

[@fredhenry101]

Modern entertainment didn't always exist. For hundreds of years there wasn't much to do when bored besides fight, make babies, and do math. So, a lot of people did math

[@shartnitazodkeesian4018]

cocaine is a hell of a drug

[@muftithecat]

pity maineking94 was talking about hemp...and not cocaine...

[@neilwilliams4420]

Paul Bernard by not getting laid enough

[@michieljames737]

Another brilliant episode. Thanks for uploading them. 👍

[@CuriosityShow]

Our pleasure. Still a few to go, and lots more at kzbin.info - Rob

[@itunedyou]

The Curiosity Show is still great to watch after all these years. Never boring! 👌

[@mykolas566]

This show is amazing, never seen this explained this way, though I do remember this principle from school and racing marbles along different types of curves.

[@nicholasvaldovino3641]

When I was taking drafting with actual pencils, drafting machines 🤭 my teacher in school actually brought that up. I don't know if they still use the same tools as back in the 90's but it was a really fun class.

[@GeoSebastians]

I got this in my recommendation. Don't know why. Nevertheless, some quality content!

[@joshuaknight6551]

Have you been mocking flat Earthers? I have. I think it is mentioned to get them here to learn basic curves and stuff

[@peetsnort]

The elites have judged you to join the magic club. You have just been invited to the inner circle

[@nocomment4848]

You guys were amazing to watch back in the day. Made education enthralling

[@iainrichardson1420]

Shame we dont get informative shows like this on TV anymore

[@danstewart8218]

this is exactly why we don't ...they made is a bit too smart we started to see the curve in politics and commerce...;D

[@bradthurkle7217]

Great show loved it as a kid. Very interesting stuff, never gets old really.

[@pikpik42]

It's like tracing the hints of the universe and it's laws. Must have been exciting to discover this and trying to understand it's relations :)

[@leekspinner]

i absolutely adore the calm presentation of the old shows

[@liftedlegend710]

love the slight bit of white noise reminds me of tv when it was good

[@Kalumbatsch]

It's not white noise but a sharp line at 15625 Hz which is the frequency of horizontal lines in PAL, 625 lines at 25 frames per second. In a CRT TV that noise is made by the flyback transformer I think.

[@willpitts9957]

Kalum Batsch wow ok smarty pants. He’s still right. Because we only used those style of television’s when he, in fact, meant the tv programs were good

[@rzeka]

@@Kalumbatsch edit: this is wrong -No, it actually is white noise. If it was flyback transformer whine it would have a more definite (and higher) pitch. You wouldn't hear the flyback transfomer on a recording like this because it's a recording, it's not being played back on a CRT.-

[@Kalumbatsch]

@@rzeka It has a very definite pitch. You can look at the spectrum in a program like Audacity, there is a sharp peak exactly at 15625 Hz, which is the horizontal frequency of PAL as it was used in Australia. There is no need to argue about it, it's the video signal.

[@rzeka]

@@Kalumbatsch Oh I see what you mean, noise from the video signal. I thought you meant it was noise directly from a CRT. Sorry for being an ass

[@nilaksh007]

If anyone wants to know, the arc length of the curve is 8 times radius os the can.

[@f1reguy587]

...the formula for circumference is 8x the radius? Not proved this, nor am I going to prove my own statement as I could be wrong anyway but at a glance, we just drew a lines path from the outside of a circle coincidentally the circumference in length, where the measuring comes into play would mean to measure the arc drawn rather than the distance travelled. This is essentially drawing “miles” compared to “nautical miles”

[@gautamtanwar6783]

@@f1reguy587 no the curve length is not the circumference if that is what you mean. This type of curve follows a special trajectory which is that of a point in pure rolling of a solid body.

[@jonsimpson6690]

The isochronous curve isn't a circle, so you can't use the arc length formula

[@grahamdavies8924]

For those having trouble with this ... "Arc length" is the distance _along the curve_ . It is understood that the curve is not part of a circle and so, yes, you can't use a formula for the arc length that applies only to a circle (duh). The circumference of the can is about 6.2832 (two pi) times its radius, but that is the length of the chord joining the ends of the curve. If we don't want to focus on the ball-bearings-meet-in-the-middle thing, we can call this curve by its proper name - a cycloid. Then we can look it up on Wikipedia and find the proof of what the original comment claims.

[@qwertyuiop3455]

@@f1reguy587 circumference only would apply in a stationary circle. The arc is from displacement of the circle.

[@photorealm]

Interesting when using the straight edge the fastest path was longer. I would have lost that bet. Very informative video, thanks for sharing.

[@Fazmagarical]

Gravity my friend 👍

[@LtPowers]

There's a reason why roller coasters don't have straight descent hills.

[@NOOne-im5vg]

I recall having to plot the path of a loci in a technical drawing class, in a similar way. Choosing a single point and plotting it's position through one revolution. This video has put a completely different aspect on that.

[@kougerat5388]

Love the fact he uses a rusty old baccy tin, I can imagine people having a fit about that nowdays lol

[@CuriosityShow]

Thanks. Curiosity Show was a national science program featuring Dr Rob Morrison and Dr Deane Hutton. It was made in Adelaide, South Australia and screened nationally in Australia as well as in Europe, Asia and Australasia (14 countries and dubbed in German for Europe) from 1972-1990. Deane and Rob intentionally used everyday items around the house (like old rusty cans) so that people could repeat the demonstrations with materials they had to hand. In 1984 Curiosity Show won the Prix Jeunesse International, the world's top award for children's TV programs. Rob and Deane are steadily uploading segments at kzbin.info Why not subscribe?

[@zapkvr]

@@CuriosityShow i was watching it the morning it came on in the 70s when it bumped Humphrey. You did that bit with the liquid nitrogen and the hose. Good times

[@gorillaau]

@@zapkvr Someone complained about Humphrey not wearing pants on a children's program. Just kidding. Possibly due to lack of educational content, or was that Fat Cat?