Scientists vote on new way to measure a kilogram

[GenesisNemesis]

Religionists are incapable of understanding that anything could possibly be arbitrary.

 

[steve_bank]

Hmmm.. you buy a kilogram of potatoes are you buying mass kilograms, or matter? Can you get a bucket of kilograms or mass?

Is a potato a physical phenomenon?

One of the most obvious ways of answering that question would be to consider if it has mass.

Folks who want to dissociate mass/weight from the inherent meaning of the word gram, are engaging in the same gobbledygook as speakpigeon's obsession over the definitional existence of infinity.

Hang in there you may earn your lab coat yet.

The point in part of SI as a global standard is that it is an unambiguous set of definitions not subject to semantics and interpretation. The opposite of philosophy and religion.

When I use the unit kilogram in an equation it has one and only one meaning, a magnitude proportional to the kg standard whatever that may be. There is no debate beyond that. It is where the philosophically inclined go off on an endless tangent. They try to find some kind of meaning where there is none to be found.

My question was a take on the old joke. Asking someone at an airport to go get a bucket of 'prop wash'. You can not get a bucket of kilograms, or inches or meters for that matter. You can get a bucket of a form of matter that weighs a kilogram.In mechanics there is something called the 'mass properties' of an object. Things like center of gravity and moments of inertia.

The term mass itself has several connotations depending on context. There are different ways to consider mass. only one possible interpretation of kilogram.

I learned dimensional analysis and units in high school chemistry. I used it for 30 years. You are not likely to develop understanding from scanning a few web pages, like the one on horsepower.

 

[steve_bank]

A law was passed mandating metric way back, but it was never enforced. Packaged foods seem to have both.

In engineering manufacturer data has been metric for a while.

 

[steve_bank]

The balance idea was great, and practical. Must be an engineer. The idea of electrical balncing goes back to the 19th century at least. The Wheatstone Bridge is used to measure unknown impedances.

https://en.wikipedia.org/wiki/Wheatstone_bridge

From the Kibble Balance link it seems like the new standard will be a relatively simple portable device, and inexpensive.

 

[Shake]

So, if my scale is in kilograms, does that mean I lost weight today? If so, I'll celebrate with some ice cream.

This is perhaps the most sensible post on this thread thus far. Even if we didn't lose weight today, I still think some ice cream is in order.

 

[Gun Nut]

I was pointing out the irony of voting on a question that science ought to be able to resolve empirically. Ask yourself, why might one scientist vote x and another vote y ?

Are they using different methods to decide? Don't they all have access to the same data?
Is this politics or science?

This is not an empirical question, it is a question purely of convention.

You mean like the definition of bats/birds?
I vote we use the bible definition.

Seriously, aren't those scientists going to use science to answer the question of which way to vote? Do we vote to decide if Pluto is a planet or not?

You are the failure of theology in American society. The bible has lots of great use... but when you try and use it where it is otherwise useless, you make the whole thing appear useless and give ammo to unbelievers.. so, stop that. Use the right tools for the job at hand.

The bible tells us that the value of Pi is 3. It is not. Bad tool for math and science for obvious reasons. It lacks mathematical precision needed for modern technology... more of a general guide... which gives you an idea, but not a correct final answer.

People like you sound like the TV commercial guy before father's day trying to sell the "the last and only tool any man needs".. the combo-knife-driver-sledgehammer-tweezers grooming gun cleaning folding tool... of course.

 

[skepticalbip]

Hmmm.. you buy a kilogram of potatoes are you buying mass kilograms, or matter? Can you get a bucket of kilograms or mass?

Is a potato a physical phenomenon?

One of the most obvious ways of answering that question would be to consider if it has mass.

Absolutely, potatoes have mass. Mass is one of the intrinsic properties of potatoes. However, the units we use to describe our measurement of that mass is completely man made and not an intrinsic property of the potato. Whether we choose to describe our measurement of that mass as grams, pounds, ounces, pennyweights, stones, etc. is an arbitrary man made system independent of the potato.

Just as your height is one of your intrinsic properties but the units of centimeters, feet and inches, hands, or cubits used to describe your height are standardized man made units independent of you.

You are conflating the intrinsic properties of an object with the units humans use to measure and describe that object.

 

[Speakpigeon]

Religionists are incapable of understanding that anything could possibly be arbitrary.

Well, nothing is really arbitrary in a deterministic universe. Scientists who have decided on the definition of the kilogramme couldn't have decided otherwise. The definition of the kilogramme is ultimately determined by the laws of nature. "Arbitrary" is just a word scientists use to annoy the "religionists".
EB

 

[Lion IRC]

You mean like the definition of bats/birds?
I vote we use the bible definition.

Seriously, aren't those scientists going to use science to answer the question of which way to vote? Do we vote to decide if Pluto is a planet or not?

You are the failure of theology in American society. The bible has lots of great use... but when you try and use it where it is otherwise useless, you make the whole thing appear useless and give ammo to unbelievers.. so, stop that. Use the right tools for the job at hand.

The bible tells us that the value of Pi is 3. It is not. Bad tool for math and science for obvious reasons. It lacks mathematical precision needed for modern technology... more of a general guide... which gives you an idea, but not a correct final answer.

People like you sound like the TV commercial guy before father's day trying to sell the "the last and only tool any man needs".. the combo-knife-driver-sledgehammer-tweezers grooming gun cleaning folding tool... of course.

Jokodo said this is not an empirical question, that we CAN vote to decide it, that it's entirely arbitrary. If it's not a scientific 'no-brainer' then why not let a conclave of Cardinals at the Vatican vote on it?

You claim the bible isn't sufficiently accurate about pi but the bible was using Lawrence Krauss' approximation maths. Krauss says 2+2=5 every now and then.

 

[Lion IRC]

Hmmm.. you buy a kilogram of potatoes are you buying mass kilograms, or matter? Can you get a bucket of kilograms or mass?

Is a potato a physical phenomenon?

One of the most obvious ways of answering that question would be to consider if it has mass.

Absolutely, potatoes have mass. Mass is one of the intrinsic properties of potatoes. However, the units we use to describe our measurement of that mass is completely man made and not an intrinsic property of the potato. Whether we choose to describe our measurement of that mass as grams, pounds, ounces, pennyweights, stones, etc. is an arbitrary man made system independent of the potato.

Just as your height is one of your intrinsic properties but the units of centimeters, feet and inches, hands, or cubits used to describe your height are standardized man made units independent of you.

You are conflating the intrinsic properties of an object with the units humans use to measure and describe that object.

It's not conflation. The intrinsic property of a gram is it's weight. The more accurately we can empirically determine its weight, the better our science will be.

We shouldn't be voting on which is the more accurate or preferred way to measure a gram.

 

[skepticalbip]

Absolutely, potatoes have mass. Mass is one of the intrinsic properties of potatoes. However, the units we use to describe our measurement of that mass is completely man made and not an intrinsic property of the potato. Whether we choose to describe our measurement of that mass as grams, pounds, ounces, pennyweights, stones, etc. is an arbitrary man made system independent of the potato.

Just as your height is one of your intrinsic properties but the units of centimeters, feet and inches, hands, or cubits used to describe your height are standardized man made units independent of you.

You are conflating the intrinsic properties of an object with the units humans use to measure and describe that object.

It's not conflation. The intrinsic property of a gram is it's weight. The more accurately we can empirically determine its weight, the better our science will be.

No it isn't. Now you are confusing weight and mass. A standard gram reference will not weigh the same at different points on the Earth and it will weigh considerably less on the Moon (less than 1/5th its weight on Earth) and will weigh nothing when freely floating in space.

We shouldn't be voting on which is the more accurate or preferred way to measure a gram.

Why not? It is a unit of measurement that humans thought up. Making it more precisely reproducible anywhere would be a great benefit for science.

 

[steve_bank]

Absolutely, potatoes have mass. Mass is one of the intrinsic properties of potatoes. However, the units we use to describe our measurement of that mass is completely man made and not an intrinsic property of the potato. Whether we choose to describe our measurement of that mass as grams, pounds, ounces, pennyweights, stones, etc. is an arbitrary man made system independent of the potato.

Just as your height is one of your intrinsic properties but the units of centimeters, feet and inches, hands, or cubits used to describe your height are standardized man made units independent of you.

You are conflating the intrinsic properties of an object with the units humans use to measure and describe that object.

It's not conflation. The intrinsic property of a gram is it's weight. The more accurately we can empirically determine its weight, the better our science will be.

We shouldn't be voting on which is the more accurate or preferred way to measure a gram.

Who is this 'we' you refer to?

Have you read the stated uncertainty of the proposed standard? If you want to get into the spirit of things talk numbers. How close is the current standards around the world to the current Paris standard they were derived from as a starting point.

It has practical meaning. if you but a kg of tomatoes in Australia how close to 1kg will it be in the USA?

Back in the 90s I worked in a group making true mass fuels flow meters for jets. More accurate fuel flow measurement the less reserves a jet is required to carry.

Once a year someone from NIST came out to calibrate nozzles we used to create different flow rates.

Ne brought a scale, a bucket, a timer referenced to the NIST time standard, and a set of weights referenced to the American primary kg standard.

He vented a nozzle into a bucket for a time and weighed the bucket on the scale. How accurate would the measurement be?

 

[Lion IRC]

The intrinsic property of a gram is it's weight and it's mass.
Happy now?

 

[skepticalbip]

The intrinsic property of a gram is it's weight and it's mass.
Happy now?

I'm always happy but you are still completely wrong and keep getting "wronger". You should study a little physics before opining on such matters.

 

[Sarpedon]

Really, this is not substantially any different than voting on whether to use imperial or metric units.

Is Lion's problem here that he thinks that since a kilogram is 1000 grams, it can't be redefined? Can we just say we are redefining the gram (which we are) and come to a happy agreement?

The reason they are saying they are redefining the kilogram instead of the gram is because, historically, they defined the kilogram and with it the gram off that piece of metal in Paris. A gram is a small unit, and having a big kilogram weight is easier to handle than a tiny gram weight.

 

[Speakpigeon]

We shouldn't be voting on which is the more accurate or preferred way to measure a gram.

And that's not what people are doing. Why are you even talking about things you just don't understand?! Can't you Google it and spend some time thinking about what is really going on instead of chasing wild goose?!
EB

 

[Speakpigeon]

The intrinsic property of a gram is it's weight and it's mass.
Happy now?

No, there is nothing intrinsic to weight. Weight depends on where you are on Earth, or even whether you are on Earth.

And there's nothing intrinsic to something arbitrary. It's a convention. A kilogram has no mass. It is a unit for God sake! It is the unit corresponding to a particular object chosen arbitrarily, for reasons of convenience. Any other object, bigger or smaller, could have done the job. It is not the kilogramme but the particular arbitrary object chosen which has a mass and scientists decided to call the value of this mass "one kilogramme".
EB

 

[steve_bank]

The intrinsic property of a gram is it's weight and it's mass.
Happy now?

I am confused now lion. Am I buying potatoes by mass or weight? What is the difference between mass and weight?

 

[Lion IRC]

The intrinsic property of a gram is it's weight and it's mass.
Happy now?

I am confused now lion. Am I buying potatoes by mass or weight? What is the difference between mass and weight?

The definition of mass and weight is arbitrary.
It's the same as the definition of a kilogram - you vote whatever you want it to be.
998 grams, 997 grams, 1002 grams...take your (scientific) pick.

 

[bigfield]

The intrinsic property of a gram is it's weight and it's mass.
Happy now?

I am confused now lion. Am I buying potatoes by mass or weight? What is the difference between mass and weight?

The definition of mass and weight is arbitrary.
It's the same as the definition of a kilogram - you vote whatever you want it to be.
998 grams, 997 grams, 1002 grams...take your (scientific) pick.

Weight is a force, and we measure it in units of force. The SI derived unit for force is the Newton: 1 N = 1 kg x 1 ms^-2. An item's weight is the product of its mass multiplied by the acceleration due to gravity: W = mg (i.e. F = ma). Since g is approximately 9.81 ms^-2 at sea level, most scales do the conversion from weight to mass for us: m = W / 9.81 ms^-2.

The number we see in kilograms is not actually our weight; it's our mass; the fact that people refer to their mass as their "weight" is simply a misconception. I didn't learn that my "weight" was actually my calculated mass until high-school science class, and I still refer to my body mass as my "weight" because that's how most people think of it.

The prefix kilo (from the Greek word χίλιοι) literally means "thousand", so a kilogram will always be exactly one thousand grams. It's not arbitrary. Kilograms and grams both units of mass, in the same way that the metre and the kilometre are units of distance.