Planck constant

The Planck constant (Failed to parse (SVG (MathML can be enabled via browser plugin): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle h} ), is named after the German physicist Max Karl Ernst Ludwig Planck. Its value (in SI units, 2006 CODATA (Ref. 1)) is:

Failed to parse (SVG (MathML can be enabled via browser plugin): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle 6.626 068 96(33)\times 10^{-34} ~\mathrm{Js}}

More recent measurements place a preliminary value at Failed to parse (SVG (MathML can be enabled via browser plugin): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle 6.626 070 95(44)\times 10^{-34}~\mathrm{Js}} (Ref. 2)

References

1. Peter J. Mohr, Barry N. Taylor, and David B. Newell "CODATA recommended values of the fundamental physical constants: 2006", Reviews of Modern Physics 80 633 (2008)
2. I A Robinson and B P Kibble "An initial measurement of Planck's constant using the NPL Mark II watt balance", Metrologia 44 pp. 427-440 (2007)