Nobody's Exactly Sure How Much A Kilogram Is Right Now

  • Published on: 27 June 2016
  • Yes, it's only micrograms of difference, but it's still really weird: until 2018, the kilogram is defined as "the weight of this physical object". So what happens when that object changes?

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  • Runtime : 3:45
  • tomscott tom scott things you might not know kilogram national physical laboratory npl watt balance kilo silicon sphere silicon sphere relative si units


  • Gaz Orr
    Gaz Orr   11 hours ago

    Who decided what a kilogram is?

  • I'm Bread
    I'm Bread   17 hours ago

    But... Metal is heavier than feather...

  • Falco
    Falco   20 hours ago

    screw it.Steel ball run, didn't even make sense but here it is. A Jojo

  • Aleksei Carrion
    Aleksei Carrion   1 days ago

    Isn't a kilogram a specific volume of distilled water?

  • Dorkmax
    Dorkmax   1 days ago

    Update: The Kilogram has now been redefined to a standard by means of the Planck Constant. It is forever consistent, unless we break physics.

  • Sean Haggard
    Sean Haggard   3 days ago

    A €2.5mm perfect kilogram sphere would be a dope desktop trinket.

  • Jason North
    Jason North   3 days ago

    I feel in the future, all measurements will be based off the constants of the universe. The length will be based on the plank length. All mesuerments in the system will be able to divide down to that. Time, instead than the secont, it will be something based of the smallest possible amount of time. (How long it takes for light to travel the plank length) mass will be based off the lightest particle. And etc. These standards are great, because there is no possibility for irratonals. Everything can be exact. Its physically impossible if it was.

  • l1lN1ckl1l
    l1lN1ckl1l   3 days ago

    Why not just use a liter of water?

  • Sun Rise
    Sun Rise   3 days ago

    If you want it fundamentally unchangeable, then use mass-energy conversion to define it

  • Miss Meme
    Miss Meme   4 days ago

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  • DrunkFox
    DrunkFox   5 days ago

    But steel is heavier than feathers.*Visual confusion*

  • Gamovie Studios
    Gamovie Studios   5 days ago

    1:05 Me with broken earbuds: it doesn't matter is it's GAY (silence) amount of mass-

  • SLASHpointO
    SLASHpointO   6 days ago

    My local drug dealer linked me to this video after ripping me off. All makes sense now. What a nice guy

  • Owen Borg
    Owen Borg   1 weeks ago

    Don’t worry I’ll solve the problemIt’s 1000 grams

  • Vanargand
    Vanargand   1 weeks ago

    This dude does not look comfortable around people

  • Johnny Booi
    Johnny Booi   2 weeks ago

    But how precise will the watt balance be?

  • Dr.Z
    Dr.Z   2 weeks ago

    Isn't a kilogram also a one Liter of water? That seems better to test against, since its global abundance.

  • Yanno
    Yanno   2 weeks ago

    You should update this video Tom. Now we only use math to find the kg value from Planck's constant

  • r0bw00d
    r0bw00d   2 weeks ago

    Stupid brain. I read the title as "Nobody's Exactly Sure How Much a Klingon Is Right Now."

  • MP Special
    MP Special   1 months ago

    I briefly worked at the International Bureau of Weights and Measurements, at the masses department, I could have a glance at the Kibble scale, that machine made to correlate the kilogram to the Planck constant so we don't rely on standard masses anymore. That thing is so precise it can catch the gravitational gradient across the room. Heck it even has to take into account its own gravitational field in the computation. They put it in in a basement room after removing the floor, so it has no physical contact with the building.

  • Charles Reiche
    Charles Reiche   1 months ago

    I never want to hear any of you metric fools talking smack to us using imperial measurements again.

  • ca-ke
    ca-ke   1 months ago

    also! weight is not the same as mass, so would the differences in gravitational field affect the second kind of measurement?

  • Hach Warwickshire
    Hach Warwickshire   1 months ago

    How much do 3 Barley Corns weigh ?Do that and you have length and mass on one ... 🤫

  • Jordan
    Jordan   1 months ago

    So it looks like they're basically using a subwoofer to measure mass

  • Casimir Paul
    Casimir Paul   1 months ago

    "That standard is always a kilogram."If I smash it into two, which becomes the new kilogram?