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Krystal n chips
16th Nov 2018, 08:25
I think it's fair to say, that, this revelation isn't going to become one of the most discussed issues for about 99.99999% of the population, although clearly it's all the fault of the French for letting the original unit of measurement deteriorate, so that could be a reason I suppose.

Of course, this years "must have ! " Christmas gift has to be a set of Kibble scales......some on JB probably already have a set of course, or are constructing their own along with various concoctions the rest of us buy from a pharmacy, but there again, possibly not.

The problem is that the unit in question is the Kg and, being British, such foreign units are never welcome....just more damned foreign intrusion !...and it won't be long before we can revert to any and all of the list below. And yes, I know, some are still in use.

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

There again, it's also possible, what with fuel loads being calculated using this measurement, crews and engineers have been knowingly endangering passengers lives by under fuelling !.....now there's a potential headline for certain rags to entice their readers with. ...

https://www.bbc.co.uk/news/science-environment-46143399

oldpax
16th Nov 2018, 10:49
Metric has been in use in the UK for years .Anyone converting to Imperial should be sacked.Metric much easier.Your not hoping for Pounds and shillings after Brexit are you!!!!

MFC_Fly
16th Nov 2018, 10:54
KnC, have you ever heard of 'The Plain English Campaign"? :rolleyes:

troppo
16th Nov 2018, 10:54
So does this make your average fat chick heavier or lighter? :confused:

Bazzo
16th Nov 2018, 10:58
...but the Kilogram is a unit of mass

Dont Hang Up
16th Nov 2018, 11:01
Metric has been in use in the UK for years .Anyone converting to Imperial should be sacked.Metric much easier.Your not hoping for Pounds and shillings after Brexit are you!!!!
Both the pound and the foot are now legally defined in terms of metric units. The "lb" is now exactly 0.45359237 kg and the foot is exactly 0.3048 metres. So while they continue in use, they are now nothing more than derivatives of the metric system.

eko4me
16th Nov 2018, 11:03
In the true spirit of pedantry, the unit is written kg - with a lower case 'k'.

Tone
16th Nov 2018, 11:08
Being a retired metrologist and a pedant I must protest at the use of Kg - it is of course kg. The electric kilogram will be much better than the old mechanical one, until it gets hacked. There may be some unintended internatiol consequences brought about by Europe being on a 50Hz supply and the USA on 60Hz.

Dont Hang Up
16th Nov 2018, 11:11
...but the Kilogram is a unit of mass
You raise a very good point.

A balance is okay for comparing two masses. Even if used in places where gravity is different the balance will still work. However, the new proposal for the kg definition is suggesting balancing a mass against a very precise electrical force. To me this means it will be dependent upon gravity at the place of measurement. And gravity is far from a constant over the surface of the Earth.

I am sure this has been considered. But it is not explained in the article.

Dont Hang Up
16th Nov 2018, 11:20
...what is also not clear is that current is normally measured using the Amp. This is a unit that is a derivative of the kg. That would make the new definition of the kg a circular argument!

Clearly they have found a way to define current independently in terms of the fundamental Plank's Constant. That is in fact the most crucial step. However, I think the article rather skims over the point.

dook
16th Nov 2018, 11:36
Being a retired metrologist…

What is a metrologist ?

Nige321
16th Nov 2018, 12:14
What is a metrologist ?

Can't get the measure of it...

Metrologists perform metrology work involving precision measurement and comparison of physical quantities such as mass, length, time, force, speed, voltage and current. They calibrate precision equipment which measures these physical units. They may also certify that outside standards of such quantities as mass and volume are correct. Congress has authorized the National Institute of Standards and Technology to set the standards of all physical quantities in the United States. The NIST was formerly called the National Bureau of Standards. Highly skilled metrologists are essential to the work of NIST.

ORAC
16th Nov 2018, 13:25
Paris is worth a Mass.......

DaveReidUK
16th Nov 2018, 13:50
What is a metrologist ?

A weather forecaster having a bad day.

ORAC
16th Nov 2018, 14:07
Do they have to do much training?

G-CPTN
16th Nov 2018, 14:12
Will the lb in my pocket still cause my trousers to droop?

Krystal n chips
16th Nov 2018, 14:44
What is a metrologist ?

Oh tsk !.....s'obvious, innit !

" quelqu'un qui travaille dans le métro parisien ".....

Or, somebody daft enough to read the UK rag of the same name.

"KnC, have you ever heard of 'The Plain English Campaign ? ".......yep,..... bollocks plain enough for you ?

treadigraph
16th Nov 2018, 14:53
bollocks plain enough for you ?

Nope. Balls would be simpler...

ORAC
16th Nov 2018, 15:28
Rocky Mountain oysters......

Mr Optimistic
16th Nov 2018, 15:31
I've still got the original furlong lying around in the garage. Bit dusty but ok. Anyone want it?

ORAC
16th Nov 2018, 15:45
Does it still have it’s chain?

Mr Optimistic
16th Nov 2018, 17:53
G-CPTN: take your hands out of your pockets and leave them where we can see them.
Orac: have I made a rod for my own back?

Mr Optimistic
16th Nov 2018, 17:55
I was hoping it was an investment and someone would buy it but I can't fathom why.

ORAC
16th Nov 2018, 18:11
Mr O,

I’m obviously not in your league, so will get back on my perch and let you take pole position.....

Mr Optimistic
16th Nov 2018, 18:15
It goes against the grain but I can't compete to that degree.

ORAC
16th Nov 2018, 18:18
There he goes. Give an inch and he takes a mile.....

Loose rivets
16th Nov 2018, 18:42
By chance, I read about this last night via The Verge.

I've been stunned by the way they get balls accurate to a few molecules, with a few rubs of a glove to take some metal off. Testing General Relativity has reached new heights. Yes, pun intended. However, nothing will impress me more than Cavendish's experiment. The intellect of mankind back then seems to exceed the science done now because they had so little to base their thinking on.

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


https://www.theverge.com/2018/11/13/18087002/kilogram-new-definition-kg-metric-unit-ipk-measurement?fbclid=IwAR3x9cmoRNVKeMa7hxgQSUEJfIciT14WaGWIm6u jeY2KiEPtWOu8D6villo

Mr Optimistic
16th Nov 2018, 19:47
Sorry, didn't mean to cause offence. I do beg your parsec, my mind's in a bit of a knot.

ORAC
16th Nov 2018, 19:57
I do beg your parsec Don’t make light of the matter - what ever angle you are trying to cover....

G-CPTN
16th Nov 2018, 21:13
Will the electric kilogramme be plug-in or hybrid?

I think we should be told . . .

denachtenmai
16th Nov 2018, 21:17
Will we be allowed to use it after Brexit?

Ascend Charlie
17th Nov 2018, 03:36
How many miles-per-kilogram-of-electrons will my Tesla get? Will I have to pay for it in cubic dollars?

MarcK
17th Nov 2018, 06:54
The barn-megaparsec is actually a usable quantity.

Hydromet
17th Nov 2018, 07:15
I wish everyone would just use the metric system, it's a dozen times easier.

Pontius Navigator
17th Nov 2018, 07:57
You're just trying to score a cheap point.

sitigeltfel
17th Nov 2018, 08:26
Just making rods for their own backs.

Mr Optimistic
17th Nov 2018, 08:31
Watt are you lot on about? It's like talking to the wife: she's an architect and I have realised after 35 years that there is always a floor in her argument.

ORAC
17th Nov 2018, 12:34
Thereby hangs a storey......

Fitter2
17th Nov 2018, 13:17
http://i64.tinypic.com/fl8ys7.jpg

(Thanks, xkcd.com)

chuks
17th Nov 2018, 13:31
There once was a US state legislature that wanted to make it so that pi = 3.0. Then some egg-head professor came along to argue against that.

Mr Optimistic
17th Nov 2018, 15:10
Some things are constant: they are as thick as two short plancks.

Pontius Navigator
17th Nov 2018, 15:25
Have an ounce of pity for those people from Troy.

BTW, you have to hand it the horse racing fraternity to use a different measure. I can't fathom it.

GordonR_Cape
17th Nov 2018, 15:46
I have always found it bizarre that a fundamental unit of anything should be a kilo-something!? None of the other units have odd prefixes. I guess its too late to change it now, like negative electron charge...

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

Argonautical
17th Nov 2018, 18:10
a foot is exactly 0.3048 metres

Also 1 inch is exactly 25.4mm which is easier to remember.

Ascend Charlie
17th Nov 2018, 19:31
BTW, you have to hand it the horse racing fraternity to use a different measure. I can't fathom it.

That shouldn't worry you fur long

Loose rivets
17th Nov 2018, 22:28
The Gravitational Constant, G, is 6.67408 × 10-11 m3 kg-1 s-2

Even the finest adjustment will be significant over the size of the Universe. Does this mean it will change size faster?

GordonR_Cape
18th Nov 2018, 02:07
The Gravitational Constant, G, is 6.67408 × 10-11 m3 kg-1 s-2

Even the finest adjustment will be significant over the size of the Universe. Does this mean it will change size faster?

The link that I posted earlier indicates that Big G is currently only known to 5 decimal places, whereas the new definition of the kilogram is proven accurate to 8 decimal places (two independent methods).

The minor uncertainty in the value of the kilogram, is overwhelmed by the difficulty of measuring the gravitational constant (originally done by the Cavendish Experiment).

Edit: Wikipedia helpfully gives the current known value of Big G as 6.67408(31)×10−11
where the uncertainty is 31 units in the 5th decimal!

Loose rivets
18th Nov 2018, 02:21
Ohhh, yes. and you've even got a man with the glove and ball.

From your link. Right, now I really will get no sleep.

In truth I spend hours on Quora giving a mention to my spacetime inflow (River) proposal whenever I think I can get away with it. Though I know it has to undergo major modification before I can get over the way in which falling bodies assume the introduction of another mass into an existing frame that's demonstrating unaffected gravitational acceleration. The aberration of starlight is another issue. Just how such an inflow of spacetime could be happening without altering the angle.

numerical values of the vacuum permeability (https://en.wikipedia.org/wiki/Vacuum_permeability), vacuum permittivity (https://en.wikipedia.org/wiki/Vacuum_permittivity), and impedance of free space (https://en.wikipedia.org/wiki/Impedance_of_free_space), which in the current definition are exact, will be subject to experimental error.[44] (https://en.wikipedia.org/wiki/Redefinition_of_SI_base_units#cite_note-Chyla-46)

Mr Optimistic
18th Nov 2018, 10:09
Bring back the aether, things were easier then. If you can con people into believing in dark matter, can't see why the aether got such a bad press.

ORAC
18th Nov 2018, 13:45
Bring back the aether Easy to produce using phlogiston as a catalyst.

denachtenmai
18th Nov 2018, 15:10
In truth I spend hours on Quora giving a mention to my spacetime inflow (River) proposal whenever I think I can get away with it. Though I know it has to undergo major modification before I can get over the way in which falling bodies assume the introduction of another mass into an existing frame that's demonstrating unaffected gravitational acceleration. The aberration of starlight is another issue. Just how such an inflow of spacetime could be happening without altering the angle.
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Loose rivets
19th Nov 2018, 00:40
Look, Sunshine. They were all the right words . . . but not necessarily in the right order. :*