Joules second

Physical unit
Unit name	Joules second
Unit symbol	${\displaystyle \mathrm {J\,s,J\cdot s} }$
Physical quantity (s)	Effect , angular momentum
dimension	${\displaystyle {\mathsf {M\;L^{2}\;T^{-1}}}}$
system	International system of units
In SI units	${\displaystyle \mathrm {1\,J\,s=1\,{N\,m\,s}=1\;{\frac {kg\,m^{2}}{s}}} }$
Derived from	Joule , second

Joule second is the SI -compliant unit of measurement of the effect with the unit symbol Js. It is the product of joules and seconds , the SI units of measurement for energy and time . According to the formatting rules of the International System of Units, the two unit symbols J and s must be separated by a space or a multiplication point. In practice, however, this space is not used.

The Joules second is the unit of Planck's quantum of action .

Planck

In 1946 it was proposed to name the unit Joule second after the physicist Max Planck , Planck (unit symbol:) . ${\displaystyle \mathrm {Pl} }$

In 1972 the Planck unit was proposed as the official SI unit for angular momentum . An angular momentum has the dimension of an effect, since in the international system of sizes it is the product of mass, length and speed and is therefore equal to the product of energy and time. However, the application did not find sufficient support.

Individual evidence

1. ↑ SI brochure
2. ↑ DIN 1301-1.
3. ^ Friedrich W. Hehl, Claus Lämmerzahl: Physical Dimensions / Units and Universal Constants: Their Invariance in Special and General Relativity . In: Annals of Physics . 2019, doi : 10.1002 / andp.201800407 .
4. ^ ^{A b} H. G. Jerrard: Dictionary of Scientific Units: Including dimensionless numbers and scales . Springer Science & Business Media, 2013, ISBN 94-017-0571-2 , pp. 106 ( limited preview in Google Book search).
5. ↑ Cutler J. Cleveland, Christopher G. Morris: Dictionary of Energy . Newnes, 2014, ISBN 0-08-096812-0 , pp. 453 ( limited preview in Google Book search).