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
I dont know, when i was 10 i made a pretty darn round snowball
Samantha LMAO 😂
🤭🤭
Not as round as mine
mines rounder
I GotNoLuck nah
1998: World's Strongest Man 2013: World's Roundest Object 2030: World's Flattest Flat-Earther 2050: World's Most Human Human
lol, i agree we just growing more inhuman
We already have most human human its jerryrigeverything the default human
more human than human
2020 COVID-19*
2100: World's last human
The tension between them is crazy
Can't blame her
Why
YES omg i was looking for somebody to say this thanks
Ty!! I was wondering if I was crazy.
I dont see it. Why do you think so?
never thought that a simple video of how round a ball is would give me so much information about so many things I never knew that existed. amazing.
Yeah like I had no idea a pound was a derivation of a kilogram
Guy: *drops it* Scientists: "I guess it's time to donate your body to science."
It's priceless anyway lmao
"We'll make something *P E R F E C T* out of it."
Hippity hoppity your life is now our property
BWAHAHAHAAAHHHAAAA
Guy: drops it Scientist: 1:32
*just holds a ball* “It feels absolutely incredible”
-_-
@@no_one866 sIGH iM aN iDioT i cOMmEnt -____-_-__-____-_--- iM sO cOOl
Deez nuts
@@yinyang1217 no one finds you funny
Yin Yang what’s wrong with commenting -_-
10:00 >Listening along doing stuff: >"as early as 2014" >Checks date >Time flies bois
"You can't have a unit which value changes!" Currencies: Well yes, but actually no.
Well yes but that's different. Money is a medium for exchanging things of value. Meanwhile the whole of science relies on the units remaining constant. Now that we've done that we can insure that measurements won't drift out of alignment over time. Which could obviously cause problems.
R u a STONK Invester
i wanted to make an argument about how the author doesnt seem to understand the concept of units. but i decided that all hope is lost. cheers
it doesn’t even look like it’s moving when he moves it with his hand
Super _ it reminded me of that one magic ball that was in tv commercials like in 2011
fushigi
fushigi lookin ass
Super _ oh god that’s trippy
Yes, I made a comment to that same point. It's easy to imagine the sphere is not rotating and his hand is just sliding around it.
Scientists: The more wrinkles your brain has, the smarter you are. My Brain:
Smooth
Round
s m o o t h
You try being a smartass and you sound like a smooth brain
No brain no pain.
4:36 We do a little bit of trolling...
Admins changed the system to prevent trolling :(
@@windowsxpmemesandstufflolchange the admins then
I always wondered why SI units were not called IS units… until now. Thank you for that among the many fascinating pieces of information here!
I think it comes from French
@@igoranisimov6549 that's exactly right (adjectives after nouns by default)
Système International en Français
Government: What did you do with the millions we gave you? Scientists: *sfeer*
Yes
68
Now 69
@@cradams1834 nice
Sphere *
When you take the Japanese foil ball challenge too seriously
lolf
Hahaha. That's really funny! God bless!
6ßY7 a 3477t747r😠😈😢😇😢😠😢 I 😤😤
Gyuu upcoming bi hyyyuuulkiiugfy💚💛💚💜💜💛💚💛💚💚👾❤👀💜👂👃💕🎱🎱💯🎱🎱🎱🎱🎱🎱🎱🎱🎱🎱🎱🎱🎱🎱🎱🎱🎱🎣🎣🎣🎣🎽🚽xoodldlllelelrlrk3ledk🛀I f🛀🛀🛀🛀cccccI9PDPOO R OFKFKFKJRJI2 r ifi i phonological l
Lol
This video, as of September 2022, is nine years old. I find the content fresh and fascinating. The locations add an extra dimension of visual interest that keeps the watcher invested in the video. You are a great presenter of scientific information, Derek.
I think the chemistry between you two is more perfect than the physics of that object
If you are curious - there was a redefinition of SI units in 2019 and the kilogram is now defined by Plank constant.
Thank you, was looking for this.
Thank you, I was wondering about that
Thanks man
Thank you man, I was looking for that
that is some valuable information
Flat earthers during this video: ‘Sorry, is there something there, I can’t see it’
😂
Amit F we see a circle
Kael Dowton 69 likes nice
@@slobiden.2593 gay
Omg you just trolled a libtard lollololililoooliloloooollolol xddxdxd XD lollso epic super epi. Epic for the win 👌👌👌👌👌🤣🤣
If I'm not mistaken the gyroscopes used in the Gravity Probe B experiment were even more accurate. I remember the sphericity when described using the Earth analogy said that the difference between the tallest peak and deepest valley would be about the height of a person. Four of them were made for the satellite. They are still in space but probably no longer as round as they used to be as they will have eventually spun down and hit the sides of the gyroscope housing as the satellite eventually lost power and helium. I'm guessing though that there might exist one or more 'flight spares'.
Correct, this sphere is actually in 3rd place, with the size analogy for the GP-B spheres being 2.4 meters, (a little bit less than 8') vs this difference of 14 meters, (slightly less than 46'). But hey, let the French have their moment.
This brings back good memories. Watch this during a good period in my life, and I'm kind of repeating that period right now
Aliens with high-tech things: *And what did you reach, humans?* Humans: *The roundest sphere.*
Hahaaha U are soo homer 🤣
Still better than nukes and weapons
@@heposlis2409 If they're truly advanced, they'd actually appreciate the scientific efforts
Aliens: *is it possible to learn this kind of power*
Why do we always see aliens more advanced than us? Why do we not see that we are more developed than them?
imagine if she was pranking him all along into thinking that it is the roundest when it's only a 10$ regular metal ball and she said it right after he went "it feels absolutely incredible"
...and boom! Found the nexus event that caused the multiverse.
@@dallascricket8532 you watch too much marvel
@@lumo5515 you understood the reference so you do too
@@lumo5515 you just got served.
@@Non-Legit he understood that reference 😉
I have always wondered why the kg is a base unit with is prefix. Thank you so much, I can stop wondering.
This is one of my favorite KZhead videos ever. Something about understanding what a "unit" is fundamentally just made me think differently
It kinda feels weird though. On one hand i don't see the exact need in this day and age for the physical object in france to still be what it is. maybe because we grew up learning the weights as numbers.
@@ryanforgo3500 it is kinda redundant noone ever needs that level of accuracy but I suppose it needs to be defined somehow. The more precise you can make the definition the less error you get from equipment. I think the point of it being so round is to do away with the physical object. They can calculate how many atoms are in the sphere and then say a Kg is the mass of this many atoms. Which will always be true
@@ryanforgo3500 if your a company making bathroom scales it can be helpful. Your rival company will be basing their measurement off the same thing as you are.
the roll of tape when I'm trying to find the seam be like:
LMAO
Except it's not the world's roundest ball it's the world's roundest cylinder
OMG AGENT PEELY AND MANCAKE FROM FORTNITE YAY BIIIIIIG FAAANNNN OMGOMOMGOMGOMGOM SHEEEEEEESH SHEEEEESH IM GETTING RIPPED TONIGHT RIP THAT EYYYYY OMGOMGOMG
@@splat6355 wut
@@pancakes8101 OMGOMGOMG MR MANCAKE IM A BIG FAN I CANT BELIEVE YOU REPLIED TO MY COMMENT OMG OMG GOSH I MISS BUTTER BARN CAN YOU SING BUTTER BARN THEME 😁😁😁😁😁😁🥰🥰🥰🥰🥰😱😱😱😱😱😱😱😱😳😳😳🤯🤯🤯🤯🤯🤩🤩🤩🤩🥞🥞🥞🥞🥞🥞🥞🥞🥞🥞🥞🥞
Scientist: its priceless Rick from pawnstars: il give you 5 bucks, im taking all the risk here
Best I can do is 62 cents and an expired gift card
Hahahaha
Hahahahahhhhhhh lmao
hahaha!!! Good one. XD
Yeah, it's not even made out of metal, just looks shiny...
9 years on and the International Prototype Kilogram has since been replaced by a kilogram based on physical constants, but such a cool video!
Can’t believe it’s been ten years since you did that video now. Time flies
When he rotates it, it doesn’t even look like its moving
You have 69 likes...sorry mate I can’t ruin it....
@@sparklyjello5405 well its at 70 now so um yh, i guess it true what they say, good things dont last forever
@@safian1232 NOOOOO SOMEONE MESSED IT UP NOW THEY MUST PAY FOR IT AAAAAAA
@@sparklyjello5405 i mean we could reach 420
@@safian1232 420?
3:38 update: in November 2018, the kilogram was finally redefined using Planck’s constant. It was the last base unit to be redefined using natural constants
That's when the world goes round, and we just stay still, like a plank!
i can't tell if this is insignificant or groundbreaking
@@randomcat5262 Both.
@@irishshawn3310 if this is a reference to that Impractical Jokers episode, then well done 😂
@@calvinhunt81 Couldn't help it!
Fun fact : The *Le Grand K* was replaced by a new definition of the kilogram based on plank constant. Which literally means that kilogram got a new definition in 2019.
For anyone wondering when he started to explain the grave the song being played is dance macabre
0:38 You know it is really round when you can't even tell the sphere is being rotated!!!
Yeah dude! That's pretty awesome.
I wonder what the world's flattest object/surface is.
Joe N. Donald Trump's hair.
EvilBonesMan_666 hahaha
Joe N. Couldn't resist. lol.
“We gave you a million euros, what did you do with it all?” Scientists: *s f e r*
s f e e r
Helf
Stolen
@@Tenite s f e e r
Rond
Just stumbled upon this video again because of KZhead shorts, turns out to be exactly 10 years ago when it came out. Wow, time flies.
the fact how much this thing could roll just goes to show how shiny it is
- Hey government can we get 1M euros for science research? - Science research? - Yes *Actually makes sphere like a boss*
Speech 100
sphere time
I completely forgot about this format
if you asked the US: "Sure but you gotta find a way to turn it into a nuke."
@@shoelicker wdym, do you know the meme format?
This whole video was just a coverup for the actual roundest object on earth. Which is that clock at 2:22
bruh moment
Painfully unfunny
Underated comment
Wow you roasted that clock. It had it coming though.
They should have used the kilogram as a stencil for it
I think that this is hand down one of the best veritasium videos and one of the best educational videos on this platform.
"Hey we have a million Euros to blow, what should we use it f-" *"World's Balliest Ball."*
If two such spheres touch each other, how big is the touching area?
Ram Page technically they aren't touching. Check out Vsauce video on "touching."
If they actually touched the area of contact would be 1 atom, that is assuming the spheres are perfectly round.
Ton even then, it would be their electrons interacting. Their nucleus wouldn't touch.
Yeah, if they were perfectly round and touched it would be 1 atom.
David even then not 1 atom. The atom's electrons on the respective spheres would interact but never physically tough each other. The nucleus nor the electrons.
They are flirting...so bad
Capcatrei I noticed that, too.
Capcatrei yeh she clearly wanted his rod in her sphere
mogur00 =)))
Why always man think like that. While woman just want to be friendly. So woman must be cold and unfriendly?
ausieking =)))
I just wanted to say: „damn I now need an update to this" then I saw your "new" Video about this Topic. Hell yeaha!
was watching this and when he said "as early as 2014" i was really shocked definitely need an update or something
In November 2018, the international scientific community voted to redefine the kilogram, affixing it to the Planck constant, a fundamental concept in quantum mechanics that will not change anywhere in the universe. The new standard went into effect May 20, 2019.
@@suedohnim8019 that's really interesting, thank you so much for the info!!
Government: “here’s a million dollars” **later** “So what’d you do with it?” Scientists: *b a l l*
"We're having a ball"
better than what the american government does with 1 million dollars
@@muchotexto4248 10:11 you must have meant a pair of them, right?
@@Subt0nixsays a weeb Your opinion doesn't matter
@@Mike-vo2rp NASA: Here you go Lockheed Martin, finish our $327.6M Mars Climate Orbiter. Lockheed Martin: Yeah, Imma just burn this over this here red planet NASA: You expect us to pay you for this? Lockheed Martin: Pretty please?
The fact that the reflection does not even change when we rotate this thing precisely shows how round it is. This is just totally isotropic.
What does isotropic mean?
@@Aunos1 China?
@@Aunos1 having a physical property which has the same value when measured in different directions.
@@mrtrashftb7657 ah, thanks. aunos was being sarcastic and negative.
@@DekuStickGamer we use Isotropic in antenna modeling 👍
7:00 I completely forgot that was even in the video by this point😂
Have they measured `pi` with it ("roundest"!), or to be more specific, determine a 1 rad angle? Currently the SI system / bipm doesn't have a "Mise en Pratique" for the radian. If we can't measure it we don't really have a unit do we...
But will it blend?
Best comment ever
+Declan Harrop sphere smoke dont breath this.....
+Declan Harrop sphere smoke dont breath this.....
Nu
Will it cereal?
*he is not holding the sphere the sphere is holding him*
The sphere is not Zlatan
James Kim lmao
We are rotating around the sphere because it’s so round.
What is this, Rusia?
James Kim looooooooooooooooooooool
The first time physics caused goose bumps on me. The moment you were talking about redefining Avogadro. Just wow
God damn, that's an old video, just realized that.
i saw this and was like yay a new veritasium video! and than i got to the end and i realized that this was 10 years ago
TEACHER: "Draw me a perfect circle..." ME: "Give me a $million first!"
lmao underrated
Upperrated
@@brainloading5543 overrated*
@@cowslave308 evenrated
@@brainloading5543 highrated
Veritasium: *“This is the world's roundest object!“* Strange crafting channels on KZhead: *“Hold my DIY aluminium foil ball.“*
@BradynLee09 i agree with you wholeheartedly
@Memes shorts beluwuga?
@BradynLee09 thats a lot of come
@Memes shorts well that was a quick reply lol
Don't forget your tin foil hat
The kilogram, symbol kg, is the SI unit of mass. It is defined by taking the fixed numerical value of the Planck constant h to be 6.62607015×10 when expressed in the unit J⋅s, which is equal to kg⋅m⋅s, where the metre and the second are defined in terms of c and Δ.
Fun fact: The Earth isn't actually round, it's oval. Since the Earth spins on an axis, gravity has warped its shape ever so slightly.
Actually it's more like a pear
and its flat towards to poles wtf flat earthers were right
bruh its geoid shape not oval
Round is 3d and oval is 2d...
@@sleeper5905 bruh lmao
"Omg big K changed weight!" "Whats it's weight now?" "A kilogram."
Precisely. It could be argued that the Big K remained the same and everything else became more massive. Since every object on earth is being bombarded with cosmic radiation, every object on earth could gain mass over time. If the big K were partially protected from radiation, it would gain less mass, and therefore appear to have less mass. All is relative. I i
More like a 1kilogram and increase to onekilogramm and fingerprint
Since it is measured using fixed units . How does it matter ?
By The Sea Aspirin Shop I don’t think that weight works like that
not anymore
Anyone else get nervous with his hand movement around the ball?
usually I am not really nervous when I touch mines.
@@lacroix9407 lol
Not like he was Louis Slotin
THIS WAS 8 YEARS AGO?
FYI the spheres in gravity probe B are 3 times rounder! Would love to see you do an update to this video. Was still great video, my kids loved it!
Hey, I have one of those spheres! A friend of mine at lockheed (Jeff ! ) gave me one of the leftover prototypes. It' a shame it's not worth a million :(
*Flat Earthers left the chat*
MrBadBricks you liked your own comment 😱😂
@MrBadBricks i like what you say
@MrBadBricks yes I do
Not true. We're proving our point by creating the perfect bowling alley.
And would women be as crazy as they are if the earth had symmetry?
For those who missed it........Le Grand K is no longer the actual kilogram. Now it is defined using the Planck constant and the new definition took effect on 20 May 2019.
So what happened to le grand k
@@Sheenifier it is kept in a vault in paris but it's no longer the definition of kilogram
@@belugathevi9296 no but I want to know like if they tossed it or put it in a museum bc right now it's just a historical paperweight
@@Sheenifier just a historical paperweight not only kilogram 3 other quantities definition were also changed
so the 1 million dollar ball is pointless?
This entire video felt like we’re cracking the code of reality.
This is one of the first YT videos I ever watched.
Imagine if a guy runs out of nowhere with sandpaper and attacks the ball
Rip
LMFAO
Grind to a dust
More Interesting Than Raiding *Area 51* Tho....
I would blame you for giving him the idea! Lol 😂
A shiny ball has more value than my life
It's priceless lol
Horus Osiris yeah which means something soo valuable and important that its price cannot be determined
***** not really
g aww
Cbnm 91201 haha :p
my brain whilst the information stated in your neural links video slides right over it
I used to live in a house directly behind Derek's head in the first shots of him in the cemetery, which is the Waverly Cemetery in the Eastern Suburbs of Sydney, Australia.
*drops ball* "oops, Can you make it again my hand slipped"
reading this makes me die inside
I actually held my breath when he picked it up with one hand and screamed in my mind: „Where is the other glove? For God‘s sake just have the other hand ready if it slips!“
@@tanyasolova8544 BOT ALERT BOT ALERT THIS IS NOT A TEST BOT ALERT BOT ALERT
B r u h
Kilogram has just be redefined as of today, may 20th 2019.
Thanks for that
Cool!
!looC
They didn't use the sphere boys
What did they use?
The sound when the locks came in was giving me chills
holding a ball: “it feels actually incredible”
Mojang: “The snow is now snowier!” This: “The sphere is now spherier!”
Ah yes the floor here is *now floorier*
true intellectuals
The grass is greener
the super is superior
We are all intellectuals here.
just googled it the definition of the kg will be redefined in 2018
.
+
WE"RE ALL GONNA DIE!
@@CC-jy4gr wait, did u forsee something?
@@sooyasos1914 Damn, I got get goosebumps reading that.. That guy really warned us XD
"Is this Spin?" - Johnny Joestar
Doyann
Thank you for the video!
69420
Omg lol
Can i have a job at dunder mifflen
Frostedturtle69 you got sour cream
There has b en a murder i do declare
@@zimmy3953 i got sour cream(if this is from a episode i forgot it)
Me watching this trying to act smart like I understand this: *hmmm yes, the kilogram is made of kilogram.*
P.s. the kilogram isn't anymore that platinum-iridium stuff
Standards lab scientist: Ah... Remember the good old days when the kilogram was defined as the weight of a chunk of platinum-iridium and they were trying to define it as the weight of a silicon sphere? Normal person: No. Standards lab scientist: Well, that was roughly a year and 4 months ago. Now they define the kilogram based on Planck's constant, the second, and the meter.
Kilograms suck, just use pounds it is 10 times better
this had no right making me laugh that hard
Lol
Are we not going to talk about how much chemistry those two had at the beginning of this video!?
i feel like they’re just being nerdy scientists getting giddy over the scientific marvel
I remember watching this but he short brought me back to see more
i legitimately thought this video was new until he said, "as early as 2014"
But it’s 2013
Same
Oough bouh oo oo ah ayeed hoo?
The kilogram has been changed and if defines by plancks constant now
Jemapsy ME TOO
I guess you can say the worlds roundest object has no point 😂😂😂
Oh no no
So it would never be a GPS cuz it can't POINT you in the right direction😂🤣😂🤣😂🤣😂🤣
NovaSeeq 😩
Ouch! That actually hurt 😂
I'm not sure weather I hate or love this pun
Every time I watch your videos, my brain gets a little bit more wrinkly. Thank you
i love that the picture of the startingscreen of this video is also in my physiks-schoolbook 😂
"You can't have a unit which changes its value" Central banks: "hold my beer"
Underrated
Hold my money printer
hahaha spot on
the likes are 669.... im sorry i cant like it mate
Fiat currencies be like. Allow me to introduce myself
So cool. She mentions the peaks a troughs scaled up to the size of the earth...but what are they on the actual sphere?, and what id the surface finish measured to? I work in engineering and normally the highest level of surface finish requirements I see is RA 0.2
"That is shockingly round." Something else that is shockingly round is the Earth. We often hear that the Earth is not a sphere but an oblate spheroid. I thought I would find something to compare it to. I chose a billiard ball and was able to google the manufacturing tolerances for billiard balls. This is 15 years ago or so. Then I looked up the numbers for the polar diameter, the equatorial diameter, the deepest ocean trench, and the highest mountain (Chimborazo, not Everest) from the center of the Earth. Long story short, if the Earth was shrunken down to the size of a billiard ball, the Earth would comfortably pass inspection as a usable cue ball. IOW, the Earth is as spherical as a cue ball. Not so oblate as they tell us. Shockingly round, indeed. (I spared you the numbers, in the hopes of keeping this short and not intimidating to those not good with numbers.)
Him saying "they may redefine the kilogram as early as 2014" has me feeling ancient bruh
Same bruh
bruhh
It caused confusion
same dude
It was only 7 years ago. How old are you, 10?
I'd laugh my Ass off if he Dropped it
+Sean Bishop lol
Seems like something conan would do.
something Linus from Linus Tech Tips would do
Sean Bishop not a haiku
Bryce Peters same, lmfao.
If it was the size of earth scratching it would create a hole that big it would create a pit so deep if you fell into it with a parachute you would be falling for 6 minutes.
Or more
For a video from 2013, this is amazing!
“That’s about the weight of a fingerprint” *HOLD UP*
No dont hold it, that will leave fingerprints
@@prakharmishra3000 I think that's why we wear gloves
Thought I started watching vsauce for a second
Honestly didn’t really know fingerprints had weight, makes sense though
@@h4rry860 gloves also leave prints.
I think one of the coolest things about this is when he’s moving it around at 0:34 and the reflection doesn’t change
This! Something about that scene had boggled me without knowing what it was. Nice catch
I thought I was tripping tbh
Yes
@Latin Games A less round object would distort the reflection as it is turned
@Meme Kong If the surface is *not* a perfectly symmetrical sphere, the reflection by the surface changes depending on from which direction you look at it.
11:42 "from cradle to grav" that was clever!
This is cool and crazy concept at the same time...!
The roundest object in the world is Vsauce's head.
GMD DeathAngel his name is Michael you disrespectful worthless pile of flesh
The Origami damn chill
I dont get it why
Anoniem no it's just cuz his bald head is round lol
yes
This is the equivalent of Rick creating true level for Morty to stand on.
It also reminded me of the Room Temperature Room from Community
i was looking for this comment lmao. that was the first thing that came to my mind when i read this video title
@@1nfinix797 a man of culture!!
@@1nfinix797 Absolutely !! I almost forgot about that, thanks !
I just love that moment in Rick And Morty, don't know why but I freaking love it
he's holding a cubemap
Lmaoo
Was the background for this El Morro in Puerto Rico?
Is it time for this object to meet the 100-ton hydraulic press?
That would be an interesting battle
fartwrangler somehow I would cringe yet still be satisfied
*PTSD*
@@mythoughts6099 not really, the ball maybe very hard, but not very durable, silicon is about as durable as glass, so no. not a battle.
Johannes S you’re too invested into something that’s not that deep