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| | BNM-INM/CNAM - M.G.A. |
 | | The two groups mass and related quantities and length are involved in a large-scale research project supported by the Bureau National de Métrologie (BNM), the objective of which is to link the basic mass unit to Planck’s constant with a relative uncertainty better than 10-8. |
 | | The experiment, known as the watt balance, could lead to a new definition of the mass unit, based on a fundamental physical constant, thenceforth considered fixed. |
 | | To this end, it has developed a polishing technique allowing one to reach a surface roughness of about 10 nm in terms of root mean square height, while at the same time guaranteeing an adjustment of the final 1 kg mass to within ±1 mg (i.e. |
| www.cnam.fr /inm/english/mga/mga.htm (1007 words) |
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