World's Roundest Object!

The world's roundest object helps solve the longest running problem in measurement -- how to define the kilogram.
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A kilogram isn't what it used to be. Literally. The original name for it was the 'grave', proposed in 1793 but it fell victim to the French Revolution like its creator, Lavoisier. So begins the tale of the most unusual SI unit. The kilogram is the only base unit with a prefix in its name, and the only one still defined by a physical artifact, the international prototype kilogram or IPK.

But the problem with this definition has long been apparent. The IPK doesn't seem to maintain its mass compared to 40 similar cylinders minted at the same time. The goal is therefore to eliminate the kilogram's dependence on a physical object. Two main approaches are being considered to achieve this end: the Avogadro Project and the Watt Balance.

The Avogadro project aims to redefine Avogadro's constant (currently defined by the kilogram -- the number of atoms in 12 g of carbon-12) and reverse the relationship so that the kilogram is precisely specified by Avogadro's constant. This method required creating the most perfect sphere on Earth. It is made out of a single crystal of silicon 28 atoms. By carefully measuring the diameter, the volume can be precisely specified. Since the atom spacing of silicon is well known, the number of atoms in a sphere can be accurately calculated. This allows for a very precise determination of Avogadro's constant.

Special thanks to Katie Green, Dr. David Farrant, the CSIRO, and the National Measurment Institute for their help. Thanks also to Nessy Hill for filming and reviewing earlier drafts of this video.

There is debate as to whether this is truly the roundest object ever created. The Gravity Probe-B rotors are also spherical with very low tolerances such that they may in fact be rounder.

Music by Kevin McLeod (incompetech.com) Decision, Danse Macabre, Scissors

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Длительность: 11:44
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Автор Reynaldo Reyes ( назад)
but boobs are round

Автор Shabarish Ramaswamy ( назад)

Автор Lvl99JinboiMan ( назад)
Hey, Vsauc-
wrong channel

Автор Spookbumps ( назад)
Can we theoretically turn it inside out?

Автор Aquagiri ( назад)
That lady scientist have a crush on you for sure ;)

Автор Goldstar279 ( назад)
You should make a perfectly geometrical square, maybe a little too perfect...

Автор Glide - TO ( назад)
Too much information

Автор Bram Meijer ( назад)
and, er... the British pound is different.. like 0.5something kilograms..

Автор Vixen The Skele-neko ( назад)
I wonder if this is made of a material that can pass through itself.

Автор Trae Williams ( назад)
the sexual nerd tension in that room is strong

Автор Troller498 YT ( назад)
And then he drops it!

Автор Jessy's Rc ( назад)
Wow people have to much times on their hands

Автор Carter H ( назад)
Who is watching is 2017

Автор AiB Oithling ( назад)
Why am I watching this I'm not even going to remember this

Автор DangerousGamer131 ( назад)
Isnt the world the roundest thing in the world

Автор Wadwizard ZOL ( назад)
Its... a ball

Автор Ski Mask ( назад)
I thought my ballsack was the roundest object..Guess im wrong..

Автор Eobard Thawne ( назад)
Spends one million dollars on protecting an arbitrary unit of measurement.

First world problems...

Автор Zachary Liu ( назад)
What's inside? Well only one way to find out

Автор - SHRED - ( назад)
The perfection👌👌👌

Автор Deniz Padır ( назад)
they couldn't find ANYTHİNG to do and make this thingamabob......seems legit

Автор Espio143 ( назад)
C'est marrant de voir des anglais prononcer des prénoms français :D

Автор Tipper ( назад)
The earth isn't round though? It's geoid.

Автор Sam Gloster ( назад)

Автор Mark Rivera ( назад)
is it safe to microwave this?

Автор Troll in the Wall ( назад)
*_Why do we need these objects in Paris when we have scales?_*

Автор linasuperdina ( назад)
the worlds roundest ball. goals

Автор Lucky RW ( назад)
but pi isnt accurate...its a little wrong

Автор JaTin RajPut ( назад)
so satisfiying

Автор Le p'tit Billy ( назад)
Yep !! French aprouved !! Ça fait plaisir de voir la culture française dans une vidéo de telle qualitée ! Thx

Автор JD ( назад)
my balls are rounder

Автор Jet Lag ( назад)

Автор Zenus BG ( назад)
1milion euros ?
Whatcha gonna di with that ?
Help people in Africa fight the femine , survive disasters or life better


Use them to make a ball , make a video how this is the roundest object and let only handful of people acctually see it !!!

Its worth it !!

And yes i watched it only to 0:55 soooo.... yeah ....

Автор LloydX ( назад)
earth is not roud tho.....

Автор The Reactor ( назад)
What's inside the world's roundest object

Автор matt ( назад)
it could be gravity changing

Автор YTEdy ( назад)
Kirsten Dunst's head is rounder. The did a comparison.

Автор gunniesack ( назад)
I've never seen an actual round pinpall.

Автор ThatKidISawTheOtherDay ( назад)
What if there was something, more rounder than a round itself, more or less, a sphere, like so defined and everything.

Автор Firestriker XX8XX ( назад)
I will sell my time machine (work in progress) for that round thing

Автор Lordz Of Fatman ( назад)
Could you also say that a kilogram is
2.2046226218 of a pound so suck these dutz

Автор The Awsum One ( назад)
Not impressed. The ball did it first.

Автор mon05 ( назад)
lol 2014? like if ur watching in 2017

Автор Beast Mode ( назад)
My tennis ball is a perfect circle

Автор Nick Byars ( назад)
Earth is not round

Автор Zack21120 musically Zack21120 ( назад)
can you do this

Автор mad Leonard ( назад)
20,000,000th view

Автор Zack21120 musically Zack21120 ( назад)

Автор Utkarsh Singh ( назад)
I am about to touch a 1kg of sphere aka Pamela Anderson boobs

Автор demir uygur ( назад)
the world is this: https://www.google.com.tr/search?q=geoid&rlz=1C1GKLB_enTR675TR675&espv=2&source=lnms&tbm=isch&sa=X&ved=0ahUKEwjpsu3KhvXSAhXma5oKHUOFDWgQ_AUICCgB&biw=1280&bih=894

Автор Joe Marley ( назад)
Were you fried when you made this?

Автор MadForCookies ( назад)
Almost as round as my balls

Автор Crvshin ( назад)
congrats on your metal ball.

Автор Jango - Agar and more! ( назад)
take the camera a bit longer away from youre head

Автор A K ( назад)
i feel this much |- -| smarter now.

Автор GemA2Gen ( назад)
Can you please don't film your face that close?

Автор Ivar Van Den Brink ( назад)
But can it survive a 100F drop covered in gummy bears?

Автор Hypicraft Hyu ( назад)
my balls is The World's Roundest Object!
p/s:it's my mom and my dad's creation 16 years ago. :v

Автор ChanyeolKaiKyungsoo Biased ( назад)
my ass is the worlds roundest object

Автор Kyle De Luna ( назад)
This video feels like vsauce

Автор Thibault Seclef ( назад)
Do a 1000 degree challenge with this

Автор dora the inhaler ( назад)

Автор momobabo50 ( назад)
vive la France

Автор gusty009 ( назад)
this was uploaded in 2013, did they actually manage to change the definition of the kg?

Автор Strixs ( назад)
I can't watch science educational videos without Micheal from vsuace

Автор Matt Lane ( назад)
Earth aint round... 20 seconds in... bad info. And whole vid is... huge waste, taking a estimate, of a estimate, of an estimate.... I mean really...

Автор Tyler Winkle ( назад)
I got a random buzzfeed video as an ad. What has the internet come to

Автор Johnny Modz ™ ( назад)
Wait a minute I'm half way through this video and have no idea why i clicked on it
*Looks At title
Oh yeah...

Автор Ben Wagner ( назад)
Can it theoretically be turned inside out?

Автор Mewstesh Mark ( назад)
Thats retartded.

My auto correct is trying to auto correct Ching into Chong

Автор Sasuke Uchiha ( назад)
Such a lie

Автор Clorox Bleach ( назад)
I came here from how to turn a sphere inside out

Автор julian hobrough ( назад)
You take an AWFUL LONG TIME to get to the POINT!!!

Автор how de do ( назад)
I don't care enough to watch the whole thing but apparently i care just enough to tell you all about it and leave a comment. Have a nice day all.

Автор Hadi masri ( назад)
this is stupid its a sphere

Автор Faiz Hanafi ( назад)

Автор HuskyTech ( назад)
Who's still watching in 2017, exactly 4 years later?

Автор Artrysa ( назад)
1:22 Because we fockin' can mate!

Автор UGin ( назад)

Автор Mike Hunt ( назад)
The roundest thing on Earth? You should see this girls ass in my culinary class....

Автор Billie Willis Ferguson ( назад)
it's just a ball. what's so special about it?

Автор Ethan Clayton ( назад)
What if a magpie stole it
Or somebody took a 1000 degree knife
Or 1000 degree round ball

Автор Jason Thomas ( назад)
put it in Minecraft

Автор junior urieta ( назад)
1 word.... Fushigi

Автор Prophet ( назад)
Why is Ampere a base unit, when electric current is charge flow per unit of time, and charge is a fundamental property of matter, but not current? Shouldn't it be Coulomb or something :/
Chances are someone already explained this to me but I forgot.

Автор Erick cole ( назад)

Автор ThatGuyFrank ( назад)
Does it has corners?

Автор Augustas Vaicekavicius ( назад)
so much sience!!!!!!!!!

Автор spliff öl ( назад)
My balls are rounder... #bequietaboutmyballs

Автор bob ( назад)
Now if I could only find my steel file....

Автор Schandorf ( назад)
Could anyone tell me the name of the music that starts at 1:38 I cannot remember the name and it's driving me crazy...

Автор Aywy plays ( назад)
What's inside the World's Roundest Object?

Автор GenoD ( назад)
lol it's just a ball

Автор dollaroubleuro ( назад)
is it only me or this exactly as spherical as my football !

Автор Jaiden Panici ( назад)
Get ready for an extensive lesson about the history of the kilogram.

Автор DA1 ( назад)
He sounds like pewdiepie

Автор Jukama ( назад)
A soap bubble is perfectly round.

Автор BadgerOnTheHuntGaming ( назад)
Someone needs to make a huge ball-point pen with it

Автор nvm ( назад)
great, now make a video about the squarest object in the world (kappa)

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