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1 kg=(h6.626 070 15×10−34) m−2 s1\ \mathrm{kg} = \left(\frac{h}{6.626\,070\,15 \times 10^{-34}}\right)\ \mathrm{m^{-2}\,s}

Why this formula appears here

Inverting that gives the unit explicitly in terms of three fixed constants: 1 kg=(h6.626 070 15×10−34) m−2 s1\ \mathrm{kg} = \left(\frac{h}{6.626\,070\,15 \times 10^{-34}}\right)\ \mathrm{m^{-2}\,s}. which the SI Brochure also writes as approximately 1.475 5214 × 10⁴⁰ times the quantity h ΔνCs divided by c squared [ 1 ] . Notice what the definition does not contain: any apparatus, any material, any temperature, any place. That is the point. “The use of a constant to define a unit disconnects definition from realization”, which “offers the possibility that completely different or new and superior practical realizations can be developed, as technologies evolve, without the need to change the definition” [ 1 ] .

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6.626 070 15×10−346.626\,070\,15 \times 10^{-34}

Denominator: 6.62607015 × 10^-34

The complete quantity below the fraction bar; it must be nonzero for this division.

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With a fixed numerator, increasing a nonzero denominator reduces the fraction. Read it with the definitions, units, and assumptions supplied by the article.

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Published contexts (1)

A symbol can carry a different meaning in another article. Each occurrence keeps its own guide and term definitions.

1 kg=(h6.626 070 15×10−34) m−2 s1\ \mathrm{kg} = \left(\frac{h}{6.626\,070\,15 \times 10^{-34}}\right)\ \mathrm{m^{-2}\,s}

Equation 1 · Metrology

The Last Artefact: Redefining the Kilogram

This equation states an equality: the expressions on both sides have the same value under the article’s assumptions.

Inverting that gives the unit explicitly in terms of three fixed constants: 1 kg=(h6.626 070 15×10−34) m−2 s1\ \mathrm{kg} = \left(\frac{h}{6.626\,070\,15 \times 10^{-34}}\right)\ \mathrm{m^{-2}\,s}. which the SI Brochure also writes as approximately 1.475 5214 × 10⁴⁰ times the quantity h ΔνCs divided by c squared [ 1 ] . Notice what the definition does not contain: any apparatus, any material, any temperature, any place. That is the point. “The use of a constant to define a unit disconnects definition from realization”, which “offers the possibility that completely different or new and superior practical realizations can be developed, as technologies evolve, without the need to change the definition” [ 1 ] .

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