Re: Data types in physics


I may have been mislead by sensationalism, but I recall a report a few weeks ago that the various international kilogram platinum-iridium masses have been showing an unexplained divergence when compared with each other.

Out of interest can anyone tell me why they use platinum-iridium for reference masses ? I assume it has good oxidation characteristics but is the any other reason for the ue of this material ?

Also, do they keep them under a vacuum ?

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Boo

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