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s

second

SI unit of time, defined as 9 192 631 770 periods of the ground-state hyperfine transitions of caesium-133

EntitySI base unitunit of timeUCUM base unitQ11574

Also known as s · seconds · sec. · sec

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Overview

All data

106 statements · 8% with external sources · numbers in brackets are citations

Measured physical quantity
Conversion to SI unit
  • 1 s
Wikidata time precision
  • 14
Conversion to standard unit
  • 3.171e-11 millennium
  • 3.171e-10 century
  • 3.171e-9 decade
  • 3.169e-8 Julian year
  • 3.169e-8 Gregorian year
  • 3.169e-8 tropical year
  • 3.171e-8 years
  • 3.803e-7 months
Show 12 more
  • 8.267e-7 fortnight
  • 1.653e-6 weeks
  • 1.157e-5 days
  • 0.0002778 h
  • 0.01667 min
  • 1,000 millisecond
  • 1,000,000 microsecond
  • 1B nanosecond
  • 10 decisecond
  • 1.157e-5 days(until 1950)
  • 3.169e-8 tropical year(1956–1967)
  • 9.19B oscillation(since 1967) class of object(s) of occurrence: caesium-133
    1
    Sources
    1. 1.“Time and frequency: SI unit of time (second) (inglés)”bipm.org/metrology/time-frequency/units.htmlRetrieved 2019-12-04
    View statement on Wikidata ↗
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On other databases

43 identifiers linking second across the web's reference databases