(Q22648)

Revision as of 22:29, 3 July 2024 by Superraptor (talk | contribs) (‎Created a new Item: second, SI unit of time, defined as 9 192 631 770 periods of the ground-state hyperfine transitions of caesium-133.)

(diff) ← Older revision | Latest revision (diff) | Newer revision → (diff)