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After two years of difficult and meticulous work examining, refurbishing, and testing the aging workhorse watt balance called NIST-3, PML researchers have used
Note:
Much more recent information is available about redefinition of the SI units. For a comprehensive general overview, see How to Weigh Everything from
Every day is a metric day at the National Institute of Standards and Technology (NIST). But that won't stop the agency from celebrating Metric Week, held