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It's nothing short of a miracle that the US made it to the moon when the imperial system's so ingrained into our culture. Oh, wait, it was a bunch of German scientists who made that possible. Nevermind... Alex
 
  
 
I didn't know that weights and currencies could be converted 1:1, that's cool! [[User:Fabian42|Fabian42]] ([[User talk:Fabian42|talk]]) 16:37, 16 November 2018 (UTC)
 
I didn't know that weights and currencies could be converted 1:1, that's cool! [[User:Fabian42|Fabian42]] ([[User talk:Fabian42|talk]]) 16:37, 16 November 2018 (UTC)
  
 
I wish they ''had'' redefined the kilogram a little bit. It would have been neat if 1 kg was exactly the weight of 1 dm^3 (1 litre) of water under one atmosphere of pressure. Right now it's soooo close. It's a good enough estimate for simple maths, but whenever you tell people that a litre of water weighs one kilogram the pedants comes out of the woodworks... [[User:Kapten-N|Kapten-N]] ([[User talk:Kapten-N|talk]]) 16:50, 16 November 2018 (UTC)
 
I wish they ''had'' redefined the kilogram a little bit. It would have been neat if 1 kg was exactly the weight of 1 dm^3 (1 litre) of water under one atmosphere of pressure. Right now it's soooo close. It's a good enough estimate for simple maths, but whenever you tell people that a litre of water weighs one kilogram the pedants comes out of the woodworks... [[User:Kapten-N|Kapten-N]] ([[User talk:Kapten-N|talk]]) 16:50, 16 November 2018 (UTC)
 
:Having thought about it, therein lies much of the joke. Originally a kg was 1 dm^3 of water at stp. But it's no longer that, so it is essentially now an arbitrary value. And being an arbitrary value, there's really no principled argument not to just redefine it as a pound. The only argument against redefining it as a pound is practical, and sentimental.[[User:Nccsa186|Nccsa186]] ([[User talk:Nccsa186|talk]]) 19:29, 8 April 2019 (UTC)
 
  
 
:You'll get pedants whenever you refer to a kilogram as weight; it's a mass.  The difference is that stuff weighs less on the Moon - or on tall mountains - although the mass is the same.  I think the article as I just read it gets away with this.  And, sure, what is the standard kilogram but a weight, that you take and weigh...  [email protected] [[Special:Contributions/162.158.91.59|162.158.91.59]] 23:57, 16 November 2018 (UTC)
 
:You'll get pedants whenever you refer to a kilogram as weight; it's a mass.  The difference is that stuff weighs less on the Moon - or on tall mountains - although the mass is the same.  I think the article as I just read it gets away with this.  And, sure, what is the standard kilogram but a weight, that you take and weigh...  [email protected] [[Special:Contributions/162.158.91.59|162.158.91.59]] 23:57, 16 November 2018 (UTC)
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::: No, it doesn't require an environment of precisely 1g, it relies on the fact that the effect of local gravity is well understood, can be measured precisely, and compensated for.  It's a fundamental aspect of the Kibble balance and you can rest assured that it hasn't been overlooked by the physicists designing it! [[Special:Contributions/162.158.134.34|162.158.134.34]] 16:38, 17 November 2018 (UTC)
 
::: No, it doesn't require an environment of precisely 1g, it relies on the fact that the effect of local gravity is well understood, can be measured precisely, and compensated for.  It's a fundamental aspect of the Kibble balance and you can rest assured that it hasn't been overlooked by the physicists designing it! [[Special:Contributions/162.158.134.34|162.158.134.34]] 16:38, 17 November 2018 (UTC)
 
::::Oh really? ''How'' would one precisely measure the local gravity? In kilograms of force? No, sorry. This is a bad method. It leads to an insoluble quandary & clearly either ''hasn't'' been thought through by its supporters, or is an intentional exploit. ''Actually'' fixing it to Planck's constant would be great, but a Kibble scale can't do that. Weighing mass against anything but another mass is foolish.[[User:ProphetZarquon|ProphetZarquon]] ([[User talk:ProphetZarquon|talk]]) 22:15, 19 November 2018 (UTC)
 
::::Oh really? ''How'' would one precisely measure the local gravity? In kilograms of force? No, sorry. This is a bad method. It leads to an insoluble quandary & clearly either ''hasn't'' been thought through by its supporters, or is an intentional exploit. ''Actually'' fixing it to Planck's constant would be great, but a Kibble scale can't do that. Weighing mass against anything but another mass is foolish.[[User:ProphetZarquon|ProphetZarquon]] ([[User talk:ProphetZarquon|talk]]) 22:15, 19 November 2018 (UTC)
:::::Local gravity is measured with a gravimeter, which is a kind of accelerometer that also compensates for tidal effects.  You can read about it here: https://en.wikipedia.org/wiki/Gravimeter [[Special:Contributions/162.158.94.2|162.158.94.2]] 15:32, 9 December 2018 (UTC)
 
  
:::I'm very happy that measuring a kilogram accurately now may require EM shielding.  EM shielding is far too rare nowadays, in this modern world of far-beyond-van-eck-phreaking.  Anything that makes shielding more prevalent and widely understood is sorely needed.  [[Special:Contributions/172.68.65.84|172.68.65.84]] 23:19, 20 November 2018 (UTC)
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:::I'm very happy that measuring a kilogram accurately now may require EM shielding.  EM shielding is far too rare nowadays, in this modern world of far-beyond-van-eck-phreaking.  Anything that makes shielding more prevalent and widely understood is sorely needed.  [[Special:Contributions/172.68.65.84|172.68.65.84]] 23:19, 20 November 2018 (UTC)
::::Amen to that! - ''Originally sent from inside a Faraday cage, but for some reason it didn't work until I stepped out.''
 
::::[[User:ProphetZarquon|ProphetZarquon]] ([[User talk:ProphetZarquon|talk]]) 20:08, 28 November 2018 (UTC)
 
  
 
Up until 1964 a litre (and therefore actually the metre too) used to be defined as the volume that water with mass 1kg takes. But this is not good for exact measurements not only because you need exactly reproducable temperature, pressure (not so problematic, because you can measure them and then calculate the divergence) and gravity (not so easy to measure, because you need an exact mass and exact masses are impossible to keep the same), but also because you need pure water free of any polutions of other stuff (hard and expensive) and even free of tiny amounts of isotopes which are deuterium and tritium (even way more expensive).
 
Up until 1964 a litre (and therefore actually the metre too) used to be defined as the volume that water with mass 1kg takes. But this is not good for exact measurements not only because you need exactly reproducable temperature, pressure (not so problematic, because you can measure them and then calculate the divergence) and gravity (not so easy to measure, because you need an exact mass and exact masses are impossible to keep the same), but also because you need pure water free of any polutions of other stuff (hard and expensive) and even free of tiny amounts of isotopes which are deuterium and tritium (even way more expensive).
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::The original proposition for a reproducible unit of mass (after the french Revolution, by Talleyrand) was that of the pound being the mass of a cubic foot of distilled water, Also the ''Grave'' (equal to our kilogram) was defined by the cubic decimetre of water by the French Commission of weights and measures in 1793. ("Le poid du pied cube d'eau étant ainsi connu, on a conclu celui du décimètre cube, ou la nouvelle unité de poids" https://books.google.nl/books?id=FufDNJHvgFEC p.274). So length and mass *were* interlinked by water.
 
::The original proposition for a reproducible unit of mass (after the french Revolution, by Talleyrand) was that of the pound being the mass of a cubic foot of distilled water, Also the ''Grave'' (equal to our kilogram) was defined by the cubic decimetre of water by the French Commission of weights and measures in 1793. ("Le poid du pied cube d'eau étant ainsi connu, on a conclu celui du décimètre cube, ou la nouvelle unité de poids" https://books.google.nl/books?id=FufDNJHvgFEC p.274). So length and mass *were* interlinked by water.
 
:Also, in E=mc², E is the energy '''at rest''' (for a stationary object of mass m), so your definition using the acceleration makes no sense.[[Special:Contributions/162.158.88.254|162.158.88.254]] 18:47, 16 November 2018 (UTC)
 
:Also, in E=mc², E is the energy '''at rest''' (for a stationary object of mass m), so your definition using the acceleration makes no sense.[[Special:Contributions/162.158.88.254|162.158.88.254]] 18:47, 16 November 2018 (UTC)
::That's not the original intent of that formula though. The modern formula is E=γmc², where m is the rest mass. But when Einstein wrote m in E=mc², he meant mass as in the measure of how much gravitational force you exert and experience... which in modern terms is γm . These days, E=mc² is only valid if γ=1, which translates to a body at rest. But that's due to the convention regarding what is meant by mass (rest mass or effective mass) changing since that formula was written, not the E being intended to neglect relativistic effects. [[Special:Contributions/172.69.55.112|172.69.55.112]] 22:56, 11 September 2019 (UTC)
 
 
Actually, for the new definition of the kilo using the Kibble balance you need to measure the gravity... [[Special:Contributions/162.158.134.16|162.158.134.16]] 17:34, 16 November 2018 (UTC)
 
Actually, for the new definition of the kilo using the Kibble balance you need to measure the gravity... [[Special:Contributions/162.158.134.16|162.158.134.16]] 17:34, 16 November 2018 (UTC)
  
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:::: No longer necessary in modern life... Which is why we should all switch to base-10 units of time! [[User:ProphetZarquon|ProphetZarquon]] ([[User talk:ProphetZarquon|talk]]) 08:36, 17 November 2018 (UTC)
 
:::: No longer necessary in modern life... Which is why we should all switch to base-10 units of time! [[User:ProphetZarquon|ProphetZarquon]] ([[User talk:ProphetZarquon|talk]]) 08:36, 17 November 2018 (UTC)
 
::::: Or we could change everything else to base 12... (I can dream, can't I?) [[User:Linker|Linker]] ([[User talk:Linker|talk]]) 18:45, 17 November 2018 (UTC)
 
::::: Or we could change everything else to base 12... (I can dream, can't I?) [[User:Linker|Linker]] ([[User talk:Linker|talk]]) 18:45, 17 November 2018 (UTC)
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:::::: I would love a base-10 time system. Especially since time=money, and money is base-10. Color me surprised a while back when my research led me to find out this had been tried in the past. They had a whole calendar system designed to renumber minutes, hours, days and weeks. I think they went to a 10 day week. Would have worked, too, except for religion. Under the new system, too many people had problems keeping track of every seventh day. SO it was scrapped. --ElectroDFW-- [[Special:Contributions/108.162.238.59|108.162.238.59]] 08:06, 22 November 2018 (UTC)  
 
:::::: I would love a base-10 time system. Especially since time=money, and money is base-10. Color me surprised a while back when my research led me to find out this had been tried in the past. They had a whole calendar system designed to renumber minutes, hours, days and weeks. I think they went to a 10 day week. Would have worked, too, except for religion. Under the new system, too many people had problems keeping track of every seventh day. SO it was scrapped. --ElectroDFW-- [[Special:Contributions/108.162.238.59|108.162.238.59]] 08:06, 22 November 2018 (UTC)  
:::::::"Swatch time" was dangerously close to a sensible set of increments. Agreed that base-10 would be better than what we use now. [[User:ProphetZarquon|ProphetZarquon]] ([[User talk:ProphetZarquon|talk]]) 20:08, 28 November 2018 (UTC)
 
  
 
Ok, I'm going to point out something.  What's a meter?  1000 milimeters.  What's a milimeter?  .....skipping the questions all the way to the end, the answer is "the wavelength of the color orange".  Or at least that's what I read.  So my question is: why orange?  What's so special about orange?  What as a species or as a solar system or as universe does the color orange have to do with anything?  [[Special:Contributions/172.68.90.10|172.68.90.10]] 21:50, 16 November 2018 (UTC) SiliconWolf
 
Ok, I'm going to point out something.  What's a meter?  1000 milimeters.  What's a milimeter?  .....skipping the questions all the way to the end, the answer is "the wavelength of the color orange".  Or at least that's what I read.  So my question is: why orange?  What's so special about orange?  What as a species or as a solar system or as universe does the color orange have to do with anything?  [[Special:Contributions/172.68.90.10|172.68.90.10]] 21:50, 16 November 2018 (UTC) SiliconWolf
 
: Orange is my favorite color. Enough said. Alex
 
  
 
: "The metre was originally defined in 1793 as one ten-millionth of the distance from the equator to the North Pole."  That's why orange.  Think of those lines from equator to pole...  and how an orange is divided in segments beneath the peel.  This is why the "Terry's Chocolate Orange" is so called, because it resembles the fruit orange.  [email protected] [[Special:Contributions/162.158.91.59|162.158.91.59]] 23:51, 16 November 2018 (UTC)
 
: "The metre was originally defined in 1793 as one ten-millionth of the distance from the equator to the North Pole."  That's why orange.  Think of those lines from equator to pole...  and how an orange is divided in segments beneath the peel.  This is why the "Terry's Chocolate Orange" is so called, because it resembles the fruit orange.  [email protected] [[Special:Contributions/162.158.91.59|162.158.91.59]] 23:51, 16 November 2018 (UTC)
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There is already one link to a Veritasium video on this subject a few coments above, and there was a new video out just before this vote, about the new units: [https://www.youtube.com/watch?v=c_e1wITe_ig The kg is dead, long live the kg]. --[[User:Kynde|Kynde]] ([[User talk:Kynde|talk]]) 15:57, 19 November 2018 (UTC)
 
There is already one link to a Veritasium video on this subject a few coments above, and there was a new video out just before this vote, about the new units: [https://www.youtube.com/watch?v=c_e1wITe_ig The kg is dead, long live the kg]. --[[User:Kynde|Kynde]] ([[User talk:Kynde|talk]]) 15:57, 19 November 2018 (UTC)
 
The title text actually made me scream in existential horror. [[Special:Contributions/162.158.79.89|162.158.79.89]]Somebody who probably has an account here but can't be bothered to log in.
 

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