Re: [Phys-L] And now WaPO Re: new kilogram, ampere, kelvin, and mole

[brian whatcott <betwys1@sbcglobal.net>]

On the banks of the Thames, down stream from Runnymede at London, Bryan 
Kibble (NPL) conceived a use for the common lab scale concept. The sort 
whose pan rises to position when you turn it on ~ an Ampere balance, in 
fact. He wanted to refine the measure of the gyro-magnetic constant. 
Later, measuring the induced voltage when dropping the coil in the known 
magnetic field and known value for g in a vacuum enclosure  eliminated 
the pesky niceties of the magnetic field size and details of the coil. 
It's a rare moment when metrology attracts some glitz - but the refined 
watt balance used for the standard mass determination was named for him. 
Posthumously, of course!

Brian W


On 11/16/2018 2:40 AM, bernard cleyet wrote:
> https://www.washingtonpost.com/science/a-massive-change-nations-will-vote-to-redefine-the-kilogram/2018/11/15/b5704b0a-e6c7-11e8-b8dc-66cca409c180_story.html?utm_term=.e9e72688d294&wpisrc=nl_todayworld&wpmm=1
>
>
> bc finds WaPo had a prelim. article:  https://www.washingtonpost.com/news/speaking-of-science/wp/2017/07/05/scientists-are-about-to-change-what-a-kilogram-is-thats-massive/?utm_term=.1be57581dd56       from last year (Bob S, and JD)
>
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