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The watt balance: a technique for implementing the new SI definition of the unit of mass

Published

Author(s)

Stephan Schlamminger, Ian Robinson

Abstract

The redefinition of the SI unit of mass in terms of a fixed value of the Planck constant has been enabled by the watt balance. Once the new definition has been adopted the watt balance technique will be able to realise SI mass over a range from milligrams to kilograms. We describe the theory underlying the watt balance technique and the measurements which turn the theory into practice to relate a macroscopic physical mass to the Planck constant with an uncertainty, which is achievable at present, in the region of 2 parts in 1E8. A number of watt balances have been built and are under construction and we compare the principal features of these balances.
Citation
Metrologia
Volume
53

Keywords

new SI, unit of mass, watt balance

Citation

Schlamminger, S. and Robinson, I. (2016), The watt balance: a technique for implementing the new SI definition of the unit of mass, Metrologia, [online], https://doi.org/10.1088/0026-1394/53/5/A46 (Accessed July 21, 2024)

Issues

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Created September 28, 2016, Updated November 29, 2019