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We can't seem to count on anything anymore...

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JohnRBaker

JohnRBaker

Mechanical
Jun 1, 2006
37,166
It appears that the standard, or "prototype", Kilogram as been mysteriously losing mass and no one knows exactly why, hence the mystery. Now this is critical since the Kilogram is the only remaining international unit-of-measure which is still based on a physical artifact, in this case, a lump of metal locked in a safe in France. So the powers-that-be are about to redefine the Kilogram once and for all, basing it on something that can be reproduced at any time, anywhere, without having to go to France to make sure that you've got it right.

For more about this issue and the proposed solution that is being considered, go to:


John R. Baker, P.E. (ret)
EX-Product 'Evangelist'
Irvine, CA
Siemens PLM:
UG/NX Museum:

The secret of life is not finding someone to live with
It's finding someone you can't live without
 
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Even if it weren't losing mass, there would still be a desire to eliminate the physical artifact. It's the only remaining fundamental unit that cannot be measured without the "standard" mass. It's sooo 1880's

TTFN (ta ta for now)
I can do absolutely anything. I'm an expert! faq731-376 forum1529 Entire Forum list
 
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So what is the lb based on??

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.
 
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Officially, the Pound is defined as a percentage of the standard Kilogram. In fact, all 'Imperial' units are now defined relative to the MKS standards.

John R. Baker, P.E. (ret)
EX-Product 'Evangelist'
Irvine, CA
Siemens PLM:
UG/NX Museum:

The secret of life is not finding someone to live with
It's finding someone you can't live without
 
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I see solder that's literally evaporated off of old circuit boards frequently. Me thinks any piece of metal could slowly evaporate due to an occasional quantum thermal event. Perhaps a cosmic ray or something gets a single surface atom to eject. Add that to the insanely accurate weighing systems we have now and I believe someone might actually notice a block of metal getting lighter over time.

Keith Cress
kcress -
 
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Note that this problem of losing weight is unique to the Paris standard, the international prototype kilogram (IPK). The other primary standards that were created more recently do not have anorexia. Given the age of the IPK, it's more likely that its composition is not what they thought it was, which is 90% platinum and 10% iridium. Both have radioactive isotopes, so it seems to me to be more likely that one or the other included radioisotopes that are decaying. Another hypothesis is that the IPK is outgassing.

The last weigh-in of the IPK showed a average of 50 ug error from 1889

TTFN (ta ta for now)
I can do absolutely anything. I'm an expert! faq731-376 forum1529 Entire Forum list
 
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If you read carefully, they had until this week, before Planck's constant is officially certain with the desired bounds to declare victory. In the meantime, BIPM still shows IPK as the standard: and these say we're not getting the new standard until next year:
TTFN (ta ta for now)
I can do absolutely anything. I'm an expert! faq731-376 forum1529 Entire Forum list
 
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You can count on your fingers, still... if you use binary notation you can count to over 1000, FWIW...

Dik
 
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we're talking 'real' numbers... not fake ones...

Just checked Wiki and apparently real numbers include -ve numbers... I'd always thought real numbers were integers above zero, but, not including zero. My apologies...

ah, Natural Numbers...
Dik
 
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Yes, integers can be either positive or negative. Back in the days of 16-bit computers and software that used integers to tag data objects, you could double the extent of your 'object' count by utilizing BOTH positive and negative integers. Now that most significant software products, like CAD systems, are based on 64-bit architectures, I suspect that there isn't be any need to ever use anything but positive integers.

John R. Baker, P.E. (ret)
EX-Product 'Evangelist'
Irvine, CA
Siemens PLM:
UG/NX Museum:

The secret of life is not finding someone to live with
It's finding someone you can't live without
 
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Confirmed by member SandCounter. "I used to count sand. Now I don't count at all."

It is a capital mistake to theorise before one has data. Insensibly one begins to twist facts to suit theories, instead of theories to suit facts. (Sherlock Holmes - A Scandal in Bohemia.)
 
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Yup... learned something yesterday...
 
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However, for some people the largest "natural" number that they are able to deal with is 10, unless of course they tend to go barefoot.

John R. Baker, P.E. (ret)
EX-Product 'Evangelist'
Irvine, CA
Siemens PLM:
UG/NX Museum:

The secret of life is not finding someone to live with
It's finding someone you can't live without
 
Upvote 0 Downvote
My ancestors came from farming folk, who used all parts of the animal. There are another 6, or so, parts that could be used, which would get you to 67.1 million and change.

Standard RGB is only 24 bits, so you could enumerate all 16.8 million RGB colors ;-)

TTFN (ta ta for now)
I can do absolutely anything. I'm an expert! faq731-376 forum1529 Entire Forum list
 
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