"I don't know if it'll take this" meanwhile having a pre-made piece of plastic perfectly fitting the thrust lines

@jonatan01i

11 ай бұрын

maybe it would sometimes collapse when he tried it

@dgphi

11 ай бұрын

That orange thing might have been a drawing tool called a flexible curve, and they might have edited out the tedious footage of the teacher bending it to the right shape.

@erikdeeNOSPELLSNO

10 ай бұрын

I stand with you- once one has done a thing a number of times- it is unlikely that one WOULDN'T know what would happen! Murphy is always there, however...

@erikdeeNOSPELLSNO

10 ай бұрын

@@creamwobbly Who is the bullshitter?

@AdamBechtol

10 ай бұрын

lol

Arches are so neat. Though the term Voussoir may be just as neat. Fun hearing them say it over and over lol.

physics has always been my arch enemy, but your videos help me understand much

@--bountyhunter--

11 ай бұрын

HAH!! I see what you did there magic man

@shoty_x1693

11 ай бұрын

I was about to be forced into learning arches but I know damn well that I'll probably regret that later. So I replied no

@SP-ny1fk

11 ай бұрын

Learning is all about building bridges

@thekadend

11 ай бұрын

Could you say these videos helped you bridge the gap in your understanding?

@seppwurzel8212

11 ай бұрын

Probably you had bad teachers, because physics is a VERY interesting topic.

A few years ago I was idly thinking about arch bridges and the fact that the Earth's surface beneath the bridge also has a curvature - granted not much, but it's there. So the longer the bridge the more the Earth curves beneath it. Take this thought to its logical conclusion and you have a bridge that goes right round the Earth and needs no supports. It becomes a giant hoop that just holds station. But an observer might look up at it and say "why doesn't it fall down?". Answer: because for that to happen, on the other side of the planet, It would have to fall up!

@nomdutilisateur

11 ай бұрын

You have a second like. I love it

@Renteks-

11 ай бұрын

Vsauce covered this in his video "Which way is down?". Ironically, this bridge would appear extremely uneven and undulating, due to having to match the forces of gravity as well.

@javelin1423

11 ай бұрын

so, like a ring? a ring across the surface of the earth that acts as a bridge

@martinsutoob

11 ай бұрын

@@Renteks- I watched the video now. When you say "extremely uneven" I think this is a huge exaggeration.. Vsauce mentions a figure of "almost 100m", but he doesn't point out that this would be stretched over many hundreds of miles and probably not detectable to the human eye. Apart from that there would be other problems with gravitational perturbations from neighbouring astronomical bodies - i.e. the Moon, the Sun, Jupiter, etc - and hence for these and for other other engineering reasons the only shape to build such a hoop would be circular. But this is all just an academic thought exercise anyway, because according to my estimates there is no building material even remotely close to being able to withstand the colossal circumferential compressive stresses that such a structure would develop. No, not even remotely. Some other engineering trickery would have to be employed. Would be a totally cool thing though.

@javiermurillo3561

11 ай бұрын

Man this is brilliant.

Arches LOVE staying up it's like their favorite thing to do

That is amazing. I had no idea arches were that resilient to movement.

Whenever I notice in the thumbnail that the documentary looks old, you know it's going to be good.

"There's strength in arches" - Prof. Joe Wilkinson, 2016.

@LucasPreti

11 ай бұрын

I opened this video with the single intent of making this joke

@corytoews5222

11 ай бұрын

"Professor"🤣

@splintmeow4723

8 ай бұрын

I’m so happy I expected this comment on this video, and happily found you 🤣

He didnt know it could take the 1kg weight at that position but you had a line ready for demonstration xD

@HartyBiker

11 ай бұрын

I have a feeling that if the arch wasn't assembled correctly, it wouldn't take 1kg, so he was more making the comment that he wasn't sure he'd assembled it correctly.

The arch only works this way if the two lower blocks are rigidly connected to each other. In this example with a shelf. Do the same experiment without a shelf, with two separate blocks at the bottom, then the thrust force will push them apart and the arch will collapse. That is why we see in medieval arch architecture, steel cross-connections between the two ends.

@user4241

9 ай бұрын

Not necessarily. If the arch has the shape of an inverted catenary, it won't collapse.

Wow amazing. Imagine a walking bridge built like this, and you can feel it move disconcertingly as you cross it! Only faith in engineering can steel your nerves 😅

@JiMwB

9 ай бұрын

Hell yeah! wobbly arch bridge!

@Francois_Dupont

22 күн бұрын

in china every bridge is like this.

Everything's in equilibrium until someone karate chops it

This gives 2009 weird side of KZread at night kinda vibes

I came here hoping to hear the word “voussoir”. I was not disappointed! (I worked at a Voussoir factory where no-one but a French software engineer called them voussoirs.)

@TheTimeCatcher

11 ай бұрын

So how did they call them?

@Jono4174

10 ай бұрын

They called them “Segments” even though they were more like “annular sectors”

@bradleyomar6300

9 ай бұрын

I came to see what the word was because the auto-subtitler gave: boosts was vusual versois fusoir vessel vussoir vuswa vusua vussoir vusoir

This is how physics should be taught!

Wow. Way better visual than anything i saw at Penn State. I would like to build some larger models. Maybe sandpaper on the surface or magnets to help initial assembly. I wonder if theres some Higher level mechanics like a Lagrangian of the centers of mass and friction at tangent points to help describe the “thrust curves” that develop

Just when you think you know an arch...there is an old school video that takes it to a whole other level!

I always wondered how the French word "voussoir" translated in English. I got my answer: it doesn't. Though in French, when it's part of an arc, the proper word is claveau (same etymology as clef, key). Voussoir is normally refering to an element of a vault.

@sporehux8344

8 ай бұрын

my new favorite word, i never knew existed.

Awesome video. Thank you.

This video looks decades older than its upload date.

@Warpedsmac

10 ай бұрын

yes.

I am taken back to my physics classes 48 years ago. Make learning fun and you have a student for life 👍🏻👍🏻

Similar principle to the spine. Nature & humanity finding similar solutions.

Children play with blocks, adults with mathematical formulas.

need more of this video!!!!!! don't just wake up the ancient roman in me like that!!!!!

@Warpedsmac

26 күн бұрын

If you look on the web for "The Arch Never Sleeps"...it does exist in its entirety on a university website....Cheers from rainy Sydney Australia

@TheRussianRob

26 күн бұрын

@@Warpedsmac well thank you!!!

It's good to see a teacher who can do more than just use chalk on a blackboard.

@iqbalindaryono8984

8 ай бұрын

Given the resources a lot of teachers would do the same

Never heard of Equilibrium before until I saw Oppenheimer. Now I hear it everywhere.

I miss the good old times, when structures worked with compression only, no rebar, no oxidation, perfection.

If some of the slats are loose between the voussoir and the abutment this would indicate the surfaces are in fact slightly UN-PARALLEL, because clearly it would not be able to be removed ...the lecturer actually confirms some of the slats were loose.

@junkbucket50

11 ай бұрын

A very interesting video, where is it from originally?

@Warpedsmac

11 ай бұрын

@@junkbucket50 if you search: The Arch Never Sleeps

@SynchronizorVideos

10 ай бұрын

Or that the slats were slightly different thicknesses, or slightly out-of-square themselves.

There always also is a little shearing. The wobbly arch could not wobble without.

I wouldn't want to drive over a bridge made of vousoirs.

The critical point is that the summation of the vectors should make up a 0 vector.

Brilliant video

Arch jenga seems kinda fun, would be difficult to set up though!

Very illustrative video. Thank you for sharing!

very important to know when you laying bricks to make a pizza oven.

_"The arch Mr Computer.."_

Ecqalibrium... New words everyday.

That wiggly arch was awesome.

It really is jigglin' tho

Polybridge training

I feel like I should be able to figure this out, but I can't. Would it work if the arch parts (in the second one) had frictionless sides?

Very interesting, Is there a complete version of the video?

That Jumpscare at the end killed me. i didnt expect it. Interesting video though

I grinned when I heard a choir at the end of this vid as if I discovered a knowledge hahaha.

😍😍😍😍 civil engineering

Should it be some special changed shape of the surface of the bricks, or I can cut the arbitrary circularity curved surface?

3:53 the holy triangle

In 8 years, this will randomly get 17M views

A wise man once said: "There's strength in arches".

This seems to continue to talk about medieval vaulted structures, what's the original film?

@Warpedsmac

Жыл бұрын

"The Arch Never Sleeps" www.open.edu/openlearn/science-maths-technology/mathematics-statistics/the-arch-never-sleeps?trackno=5

@nicolasramirez3944

Жыл бұрын

@@Warpedsmac Thanks!!!!

@Warpedsmac

Жыл бұрын

@@nicolasramirez3944 Always happy to share resources with other Engineering teachers. Cheers from sunny Australia!

thanks a lot for item question！

Why the fuck am I watching this at 2am, I have to get up for work in 4 hours..

@massimookissed1023

8 ай бұрын

At least when you get to work, *_one_* of you will know how arches stay up.

I'm currently on a youtube binge / rabbit hole, but this was very informative and interesting. I've always had an intuitive sense of forces in structures, but seeing the force vectors and the thrust line over a whole arch is very interesting, and kind of makes me want to program a physical simulation to represent different weights and thrust vectors over arches.

@ArtKM

9 ай бұрын

most informative youtube bing ever. nice.

The only thing I was able to pick up was that one part is called a Vousuoouuoouuoaaar.

Does thrust require a change in mass to not equal zero ?

complete documentary?

Does anyone know which university this is ?

I am not sure if at 2:40 the picture is complete: Aren't there frictional forces at both contact points too? - Intuitively, I would guess the whole arc would not be stable if the surface (of the contact points) would be (ideally) slippery.

@theiigotriangularround4880

9 ай бұрын

I guess it would cause there is a vertical component of normal reaction too on both sides

@joshdaly2343

7 ай бұрын

I think there are no major frictional forces in this static system. A friction force perpendicular to the thrust line would result in rotation of the block, we can see this when he adds a weight and all the blocks rotate to a new stable position.

@sakudoo

7 ай бұрын

@@joshdaly2343 Try to build the arch using slippery soap blocks. I am pretty sure it will not hold. Generally, the two planes defined by two contact points on a block are not parallel, hence the two forces will create an outward (or may be rarely an inward) force expelling the block. Yes, this is countered by the gravity of one block, but I am pretty sure that there are also fricitional forces at each of contact points.

@joshdaly2343

7 ай бұрын

@@sakudoo if the soap blocks had the same shape and density as the wooden blocks in the example, then arranged in the same shape they would still hold the arch. It would be very hard to do not (mainly) because the lack of friction, but the fact that there's only one "thrust" line for a particular arrangement of blocks. That's why the arch changes shape when a weight is added so it reaches its unique thrust line whete there's no friction.

Interesting

Hmmm… If the voussoir contact faces were slightly concave, and the material slightly compressible, would that make an arch more stable?

@GundamReviver

11 ай бұрын

Interesting thought, I figure that would mainly force the material to be under constant pressure in thr tops and bottoms, eventually thst would weather away until the forces are more spread out again.

@dangeary2134

11 ай бұрын

@@GundamReviver my logic was to induce a prestress into the material, and make it more stable. The idea being just the opposite of the convex faces. This would enhance resistance to not only the linear stress, but to lateral and torsion stresses. No swing, no twist, no bounce. Seems to make sense.

@dangeary2134

11 ай бұрын

@@GundamReviver you are a college student, up at this hour, aren’t you??

@GundamReviver

11 ай бұрын

@@dangeary2134 nah, but did start out with a degree in engineering stuff 😂 I figure you are correct in that it would have increased regidity since indeed it would be pre stressed, but thst added hardness would Probabaly mean the "points" pushing against each other would get immense force on them and break and crumble quicker. Also it's like nearly afternoon here, haha, welcome to the internet: it's always daytime somewhere.

2:30 shouldn’t there also be friction ? Or do the long blue arrows represent the sum of normal and friction?

@eragon78

11 ай бұрын

There are two types of friction. Normal friction requires movement to be occurring which isnt happening in this situation, and then Static friction which resists initial movement between the blocks slipping. Static friction would just resist any slipping and equally cancel it out. While it does technically exist in the model, it doesnt actually have any notable effect and so it can be pretty much ignored for the sake of simplicity. It only really matters if the slipping force is enough to overcome the static friction.

All here for the voorswaw, say "Aye"!

Now I want to play jenga for stonemasons

Friction is also there

No mention of a keystone?

What determines the direction of the arrows though?

youtube is weird like this, video came out 2 years ago, most comments are from this week

❤

I diеd from the instant transition from science to religion at the end 😅

How we Build an arch under ground? -anwseer fast pleas

@massimookissed1023

8 ай бұрын

Either cut an arch-shaped passage, or build an arch in a bigger excavated space, and back-fill with concrete.

I just got here from watching Anime. Now i understand about the devil fruit...

My gf forms a perfect ark

just like jenga

nobody mentioning how he just faded into the ether

Is there no friction at work parallel to the surface in the arch with strangely shaped blocks?

@xy4489

10 ай бұрын

Had same question. I think you could add the friction forces to the three forces they drew, and add more terms to the equilibrium equation. But, those terms will cancel out. The component of gravity perpendicular to the surface equals the normal force they have drawn, and the component of gravity parallel to the surface equals the friction force, neither of which they drew. At both left and right points. So, my guess is that friction is indeed there and critical to the arch. I didn't look it up though, so this might be bogus.

@xiaojiang2610

9 ай бұрын

There is. The video is misleading. Any undergrad student should point out that normal force is perpendicular to the contact surface in case 1 where cardboards were used for top bricks. Thus friction force introduced by normal force is used to counter gravity. I was so surprised no one pointed it out.

@joshdaly2343

7 ай бұрын

​@@xiaojiang2610how can a normal force, which is perpendicular to the surface, introduce a friction force, which is parallel to the surface? The whole point of arches is that they act in pure compression, hence there is no need for friction force. For the second arch in the video, if there were friction forces, the blocks would rotate (as they do briefly when he adds a weight and they come to equilibrium in a new shape with zero friction forces)

Is there any civil engineering faculty or science fac.?

I don't know if it's been asked before, but what is this from?

So there *is* actually strength in arches? Joe Wilkinson was right

Anyone else surprised when one of the students gave a good answer?

Full link of video

I use Arch btw

Никогда у вас не получиться изготовить в идеале точки соприкосновения, то ,что несут они разные (переходящие) нагрузки_это Да, но приходится вернуться в начало этого предложения

forsen

It's nice to see that Half-life anouncer still has a job

thx

I use arch btw

Watch a few clips of NL playing poly bridge and I get this recommended

@Warpedsmac

10 ай бұрын

It's an interesting video...if you like architecture and arches....Cheers from Australia.

I hated these videos in high school and crave them now

@Warpedsmac

9 ай бұрын

Nice to hear Potater...as I was once one of those high school teachers showing 'em!! Cheers from sunny Australia

I thought the forces in an evenly loaded arch followed a catenary (cosh(x)) curve. Isn't that mathematics?

@eddarby469

11 ай бұрын

That is the answer for an infinitely flexible member like a cable. But the stiffness necessary to keep an arch from buckling will allow shear and bending forces to develop. This alters the mathematical solution.

I use Arch btw.

What about Arch Linux then

i use arch btw

I mean this isn't really surprising at all... you could just have a smaller arch... smaller meaning thinner...

Must have a good line of thrust

I use arch linux btw

why are they calling the stones with some french word?

@panda4247

9 ай бұрын

@@gregoryford2532 but why? don't tell me the English people did not have arches until the French came. The word "keystone" is English, so why having a weird French word for the other stones in the arch?

Thrust..

نسال دكتور وليد ارناؤط

@Warpedsmac

11 ай бұрын

And what did the doctor have to say?

ಇಂಜಿನಿಯರಿಂಗ್

@mediocreman6323

11 ай бұрын

According to Google-Translate this word means _engineering._

Brilliant. Why can't all civil engineering teachers be like that? They aren't because they will have to work harder before coming to class.