2073: "Kilogram"

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2073: "Kilogram"

Postby Eutychus » Fri Nov 16, 2018 4:20 pm UTC

Image
Title text: I'm glad to hear they're finally redefining the meter to be exactly three feet.

I'd like to see the spelling "Kilogramme" universally adopted.
Last edited by Eutychus on Fri Nov 16, 2018 7:19 pm UTC, edited 1 time in total.
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Re: 2073: "Kilogram"

Postby anu3bis » Fri Nov 16, 2018 4:29 pm UTC

In my Starfinder campaign, I redefined a meter to 5 feet, so all the little squares on the maps would be one meter.

How big is the radius on that fireball? 4 Absalom Meters.

It's amazing, the prescience of the Ancients of Golarion for building all their structures in meter increments.

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Re: 2073: "Kilogram"

Postby roderik » Fri Nov 16, 2018 4:32 pm UTC

Now I wonder, would the pound remain defined as it currently is? for a wonderful mess of recursive definitions leading to nowhere.

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Re: 2073: "Kilogram"

Postby krabcat » Fri Nov 16, 2018 4:39 pm UTC

that really does make things easier now 1 kilogram is exactly equal to 0.45359237 kilograms

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Re: 2073: "Kilogram"

Postby ParisNorway » Fri Nov 16, 2018 4:40 pm UTC

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Re: 2073: "Kilogram"

Postby J%r » Fri Nov 16, 2018 5:46 pm UTC

Sounds like we might lose another spaceship to unit conversion errors.

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Re: 2073: "Kilogram"

Postby Soupspoon » Fri Nov 16, 2018 5:49 pm UTC

krabcat wrote:that really does make things easier now 1 kilogram is exactly equal to 0.45359237 kilograms

Or €1.12.

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Re: 2073: "Kilogram"

Postby qazsedcft » Fri Nov 16, 2018 6:01 pm UTC

I have a better proposal. Redefine:

3 feet = 1 meter
1 mile = 3000 feet

;)

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Re: 2073: "Kilogram"

Postby jozwa » Fri Nov 16, 2018 6:01 pm UTC

"And also the pound is redefined to equal pn2/4*f2/(gv)*h"

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Re: 2073: "Kilogram"

Postby orthogon » Fri Nov 16, 2018 6:07 pm UTC

Soupspoon wrote:
krabcat wrote:that really does make things easier now 1 kilogram is exactly equal to 0.45359237 kilograms

Or €1.12.

Maybe after the new definition kicks in, the French will sell us "le grand K" cheap. We could then saw it up to make two British Standard Pounds and have nearly a hundred grams of platinum left over to put towards the Brexit settlement. The new, proudly independent Pound would be forever freed from the tyranny of Brussels.

What to do with the two pounds? We could have one for the Remoaners and one for the Brexiteers. Or we could sell one to Trump so the US can have slightly different pounds to go with the slightly different gallons.
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Re: 2073: "Kilogram"

Postby cellocgw » Fri Nov 16, 2018 6:28 pm UTC

How many bitcoins per kg?
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Re: 2073: "Kilogram"

Postby Moose Anus » Fri Nov 16, 2018 6:31 pm UTC

orthogon wrote:Maybe after the new definition kicks in, the French will sell us "le grand K" cheap.
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Re: 2073: "Kilogram"

Postby Quizatzhaderac » Fri Nov 16, 2018 6:56 pm UTC

But which kind of pound? Avoirdupois, Roman, Troy, Tower, Merchant, American, or London?
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Re: 2073: "Kilogram"

Postby The_Alchemist » Fri Nov 16, 2018 6:57 pm UTC

I keep thinking it would be nice to redefine the second so that there are 10 hours/day, 100 minutes/hour and 100 seconds/min.

Small is small, right? What could possibly go wrong? :P

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Re: 2073: "Kilogram"

Postby GlassHouses » Fri Nov 16, 2018 7:17 pm UTC

The_Alchemist wrote:I keep thinking it would be nice to redefine the second so that there are 10 hours/day, 100 minutes/hour and 100 seconds/min.

Small is small, right? What could possibly go wrong? :P

It's been tried. Didn't catch on.

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Someguy945
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Re: 2073: "Kilogram"

Postby Someguy945 » Fri Nov 16, 2018 7:43 pm UTC

Just in case anyone was out of the loop, this comic was inspired by a recent vote to adjust the definition of the kilogram.

They're not actually changing how much a kg is, since that would be insane. They are keeping the end result but changing how you arrive at that result.

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Re: 2073: "Kilogram"

Postby ijuin » Fri Nov 16, 2018 7:50 pm UTC

Wasn’t the original basis of the kilogram equal to the mass of one thousand cubic centimeters of pure water at one gravity under standard atmospheric conditions?

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Re: 2073: "Kilogram"

Postby commodorejohn » Fri Nov 16, 2018 8:09 pm UTC

Words cannot describe how much I want this.
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Re: 2073: "Kilogram"

Postby CardcaptorRLH85 » Fri Nov 16, 2018 8:10 pm UTC

Someguy945 wrote:Just in case anyone was out of the loop, this comic was inspired by a recent vote to adjust the definition of the kilogram.

They're not actually changing how much a kg is, since that would be insane. They are keeping the end result but changing how you arrive at that result.


I was about to post something similar but, they are actually changing the end result slightly. The vote actually took place today (which explains the timing of the comic) but the change doesn't occur until May 20, 2019 (which explains Black Hat Guy's timing in his second sentence). They've decided to set Planck's Constant to an exact value (6.62607015×10^-34 kg⋅m^2/s it's currently slightly imprecise depending on when and where it's measured). This will cause Kilogram measurements to float a bit around the ~38th decimal place or so.

As my first URL notes, a number of other units and constants also had to be altered because of this change. The Kelvin, Avogadro's Constant, the ampere, the mole, among others. This was a very long undertaking done in order to fix a problem created by having a unit that was (and technically is) still defined by a physical object rather than by the universe itself.

ijuin wrote:Wasn’t the original basis of the kilogram equal to the mass of one thousand cubic centimeters of pure water at one gravity under standard atmospheric conditions?


You wrote this while I was typing my comment but, it wasn't at STP. It was water at 0°C so, just as it was becoming ice. Given how water acts (and the fact that a liter of water is not exactly one modern Kilogram under those conditions) that's not a good idea.

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Re: 2073: "Kilogram"

Postby yakkoTDI » Fri Nov 16, 2018 8:16 pm UTC

Reminds me of this.
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Re: 2073: "Kilogram"

Postby mfc » Fri Nov 16, 2018 8:18 pm UTC

Reminds me of my least-favourite 'teacher lie':

"A pint's a pound, the world around".

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Re: 2073: "Kilogram"

Postby DavidSh » Fri Nov 16, 2018 8:50 pm UTC

Indeed, what with inflation and all, I doubt you can buy beer so cheaply anywhere these days.

(Besides the question of what kind of pound, there is also the question of what kind of pint.)

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Re: 2073: "Kilogram"

Postby Steve the Pocket » Fri Nov 16, 2018 9:18 pm UTC

Ironically, pints are one unit of measurement us yanks don't much bother with. The standard unit of measurement for beer in America is the beer.
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Re: 2073: "Kilogram"

Postby Quizatzhaderac » Fri Nov 16, 2018 9:42 pm UTC

yakkoTDI wrote:Reminds me of this.
To understand all of the English distance units, use this handy-dandy chart.
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Re: 2073: "Kilogram"

Postby RogueCynic » Fri Nov 16, 2018 9:50 pm UTC

Someguy945 wrote:Just in case anyone was out of the loop, this comic was inspired by a recent vote to adjust the definition of the kilogram.

They're not actually changing how much a kg is, since that would be insane. They are keeping the end result but changing how you arrive at that result.


So, they are adjusting their equations to to get the result they want. Figures don't lie, but liars figure.
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da Doctah
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Re: 2073: "Kilogram"

Postby da Doctah » Sat Nov 17, 2018 12:01 am UTC

The metric system is unnatural anyway. There's a reason God made the diameter of the sun in miles ten times the number of seconds in a day.

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Re: 2073: "Kilogram"

Postby Flumble » Sat Nov 17, 2018 1:21 am UTC

Quizatzhaderac wrote:To understand all of the English distance units, use this handy-dandy chart.

My little cousin says 3*2*100*10 ≠ 8060, but surely an entire country knows better than someone who just learned long multiplication. :roll:
(also I hate the cubit. It has "cube" in the name but isn't a unit of volume.)

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Re: 2073: "Kilogram"

Postby Mikeski » Sat Nov 17, 2018 1:26 am UTC

yakkoTDI wrote:Reminds me of this.

Obligatory:

There are two kinds of countries in the world. Those that have put a man on the moon, and those that use the metric system.

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Re: 2073: "Kilogram"

Postby qvxb » Sat Nov 17, 2018 1:56 am UTC

Has BHG updated the Wikipedia article?

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Re: 2073: "Kilogram"

Postby keldor » Sat Nov 17, 2018 2:28 am UTC

Flumble wrote:
Quizatzhaderac wrote:To understand all of the English distance units, use this handy-dandy chart.

My little cousin says 3*2*100*10 ≠ 8060, but surely an entire country knows better than someone who just learned long multiplication. :roll:
(also I hate the cubit. It has "cube" in the name but isn't a unit of volume.)


That's a really good example of one reason why these units have historically drifted. 3*2*100*10 is just a bit more than 1% off from 6080, so the phrase "close enough" comes to mind. Especially when you're dealing with obselete units that they historically wouldn't necessarily have been able to measure that accurately anyway.

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Re: 2073: "Kilogram"

Postby Plasma Mongoose » Sat Nov 17, 2018 4:16 am UTC

If anything, they should redefine the American pound to make it equal one kilo, that way women can feel better when they weigh themselves, imagine going from being 200 lbs to 90 lbs with one easy conversion.
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Re: 2073: "Kilogram"

Postby commodorejohn » Sat Nov 17, 2018 4:32 am UTC

Steve the Pocket wrote:Ironically, pints are one unit of measurement us yanks don't much bother with. The standard unit of measurement for beer in America is the beer.

Yes and no. You buy beer at the store in discrete units (or packs thereof,) which are usually 12 oz., but may be a US pint (16 oz.) or a larger semi-standard size (~25 oz.) but may be whatever the hell the brewery felt like selling (there's at least one brand - I think Red Stripe? - that comes in 10 or 11 oz. bottles.) However, at a bar or a restaurant where beer is on tap, you typically get it in either a US pint or an imperial pint (20 oz.) unless you're getting something strong (Belgian ales in particular seem to have a fairly standard 10 oz. pour.) And at a brewery, you may even purchase beer in refillable "growlers" (64 oz.)
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Re: 2073: "Kilogram"

Postby Pfhorrest » Sat Nov 17, 2018 5:29 am UTC

Are these oz as in 1/16lb, or floz? And are floz standardized between US and imperial systems? (e.g. is a US pint exactly 4/5ths an imperial pint?)
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Re: 2073: "Kilogram"

Postby rpgamer » Sat Nov 17, 2018 6:38 am UTC

I would just like to say that this comic made me viscerally shudder.

But I did enjoy learning from this thread that the kilogram is finally receiving a makeover. Bit disappointed that it had to come from fudging some other constants (they're supposed to be universal constants, can they even do that?). Kinda sounds like scientists were so fed up with the problem of the kilogram constant that they just sorta gave up and acquiesced to a constant that was "close enough" that will at least remain... constant.

Can't say I'd blame them, really.
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Re: 2073: "Kilogram"

Postby orthogon » Sat Nov 17, 2018 9:45 am UTC

rpgamer wrote:I would just like to say that this comic made me viscerally shudder.

But I did enjoy learning from this thread that the kilogram is finally receiving a makeover. Bit disappointed that it had to come from fudging some other constants (they're supposed to be universal constants, can they even do that?). Kinda sounds like scientists were so fed up with the problem of the kilogram constant that they just sorta gave up and acquiesced to a constant that was "close enough" that will at least remain... constant.

Can't say I'd blame them, really.

They're not really fudging the constants: they're turning the definition around. Previously they defined the kilogram based on a particular lump of metal, and measured the value of Planck's constant experimentally to a certain accuracy. Now they define Planck's constant as having a particular exact value (the same value they found by experiment) and measure the mass of any given object experimentally. This implicitly defines the kg.

They did the same thing a while back for the metre. They had the second defined already, but the metre was the length of a stick in Paris. They measured the speed of light as accurately as they could based on the old definition, then they turned it around and said "the speed of light is (299xxxxxx) metres per second. The second was defined, the speed of light is a universal constant, so the metre is now defined implicitly.
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Re: 2073: "Kilogram"

Postby Kit. » Sat Nov 17, 2018 9:52 am UTC


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Re: 2073: "Kilogram"

Postby DavidSh » Sat Nov 17, 2018 5:20 pm UTC

Pfhorrest wrote:Are these oz as in 1/16lb, or floz? And are floz standardized between US and imperial systems? (e.g. is a US pint exactly 4/5ths an imperial pint?)

These are fluid ounces. The US fluid ounce is about 4% larger than the Imperial fluid ounce. The Imperial fluid volume system is based on the volume of a standard weight of water at some standard temperature and pressure. The US fluid volume system is based on cubic inches.

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Re: 2073: "Kilogram"

Postby commodorejohn » Sat Nov 17, 2018 5:24 pm UTC

Pfhorrest wrote:Are these oz as in 1/16lb, or floz? And are floz standardized between US and imperial systems? (e.g. is a US pint exactly 4/5ths an imperial pint?)

Fluid ounces. And I hadn't even considered that - devilishly enough, even that measure is slightly different. According to Wikipedia, an imperial fluid ounce is about 28.41 ml, while a US fluid ounce is about 29.57 ml, a difference of about 4.08% or so. So a US pint is about 83.27% of an imperial pint.

Edit: beaten!
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Re: 2073: "Kilogram"

Postby rmsgrey » Sat Nov 17, 2018 7:28 pm UTC

rpgamer wrote:I would just like to say that this comic made me viscerally shudder.

But I did enjoy learning from this thread that the kilogram is finally receiving a makeover. Bit disappointed that it had to come from fudging some other constants (they're supposed to be universal constants, can they even do that?). Kinda sounds like scientists were so fed up with the problem of the kilogram constant that they just sorta gave up and acquiesced to a constant that was "close enough" that will at least remain... constant.

Can't say I'd blame them, really.


Under the previous definition, the relevant "constants" weren't actually constant - the standard kilogram is known to have changed mass over time (exactly how much is unclear) and the various reference copies of it have also changed mass at different rates - so any previous measurements used to calculate the fundamental constants were wrong (depending on how the reference kilogram for those measurements had changed relative to the standard kilogram) and also varied over time.

So, as Orthogon says, they're replacing the current definition of the kilogram with a new one so that, as nearly as they could measure, everything keeps the same mass. At the same time, they're updating various constants that depended on the exact value of the kilogram, some of which were already known to be wrong since they'd been based on old values for the kilogram, and not updated to account for more recent changes in the standard kilogram's actual mass.

For practical applications, it won't make a difference; for experimental physicists, it'll mean it's easier to recalibrate their equipment to keep it correct since it'll be possible by performing an experiment with a known result rather than requiring access to a specific chunk of metal (or an extremely high-quality copy).

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Re: 2073: "Kilogram"

Postby Soupspoon » Sat Nov 17, 2018 8:01 pm UTC

This assumes the fundamental constants do remain constant, of course. I know people are on the look-out for such temporal/spacial differences (assuming that they haven't been seen but been misidentified as cosmic inflation or somesuch) but we could be exactly on the verge of getting good enough to finally detect the creep.

It's not quite as hard to imagine as what might cause Pi and/or e to notably drift… :twisted:


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