Image: Unit relations in the new SI

Description: Metrological dependencies between the different base units of the SI system of units as agreed to on 16 November 2018. This removed the International Prototype of the Kilogram as the definition. The chart shows the fundamental physical constants used to define the base units:

s - the frequency of the cesium hyperfine transition (ΔvCs) for the second,

kg - the Planck constant (h) for the kilogram,

mol - the Avogadro constant (NA) for the mole,

cd - the sensitivity of the human eye (Kcd) for the candela,

K - the Boltzmann constant (kB) for the kelvin,

A - the elementary electric charge (e) for the ampere,

m - the speed of light (c) for the metre.

Arrows are shown in the opposite direction compared to typical w:dependency graphs, i.e. a→b{\displaystyle a\rightarrow b} in this chart means b{\displaystyle b} depends on a{\displaystyle a} (a{\displaystyle a} is used in the definition of b{\displaystyle b}).

Generated from a Mathematica notebook at https://github.com/episanty/SI-unit-relations
Author: Emilio Pisanty
Usage Terms: Creative Commons Attribution-Share Alike 3.0
License: CC-BY-SA-3.0
License Link: http://creativecommons.org/licenses/by-sa/3.0/
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