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Second

The second (symbol: s) is a unit of time derived from the division of the day, first into 24 hours, then into 60 minutes, and lastly into 60 seconds, for a total of 24 × 60 × 60 = 86400 seconds per day. That definition, based on .mw-parser-output .frac{white-space:nowrap}.mw-parser-output .frac .num,.mw-parser-output .frac…

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Symbol
s
Unit of
time
Unit system
SI

Topics to explore

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Overview

Uses

Clocks and solar time

Events and units of time in seconds

Other units incorporating seconds

Timekeeping standards

History of definition

Future redefinition

SI multiples

Advanced semantic analysis

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Map overview Semantic statistics

Second

Nodes90
Edges89
Triples130
Avg. degree1.98
Density0.022222
Components1

How this topic connects Entity context

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Second

Top relations

related to Future redefinition · 17
Second → CsFO2, Delta, Hz, In, International Atomic Time, IT-CsF2, NIST-F2, NPL-CsF2, Optical, PTB-CSF2, Q-factor, Ramsey, SU, SYRTE-FO2, The, These, They
related to Fraction of solar day · 16
Second → By, Din, During, Europe, Fremersdorf, Hesse, In, It, Jost Bürgi, Mechanical, Orpheus, Taqi, The, Tycho, Tycho Brahe, William
related to External links · 15
Second → Archived September, Canada, Cesium, Definition, High-accuracy, KOfficial BIPM, National Physical Laboratory, National Research Council, Optical, Our, Scales, SLAC, Time, Trapped, Wayback Machine
related to Fraction of an ephemeris year · 13
Second → Earth, Earth's, IAU, In, It, Metrologists, Newcomb's Tables, Newtonian, Sometime, Sun, The, The Earth's, This
related to Events and units of time in seconds · 8
Second → For, Fractions, Gregorian, In, It, Julian, Multiples, Some
related to Timekeeping standards · 8
Second → Civil, Coordinated Universal Time, Earth, International Atomic Time, TAI, The, This, UTC
related to Atomic definition · 7
Second → Atomic, Even, Radiation, Since, The, Therefore, This
related to Uses · 7
Second → An, Analog, Camera, Digital, Multiples, SI, Though SI
related to Clocks and solar time · 5
Second → Earth, Earth's, Sun, That, The
related to Sexagesimal divisions of calendar time and day · 5
Second → Civilizations, Conceptual, Middle Ages, Sundials, There

Important terminology Word statistics

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Important terminology

time clocks seconds units clock minutes year definition frequency atomic unit day system si caesium hours based rotation also defined

Entity relationships Subject–Predicate–Object triples

SubjectPredicateObjectConfidenceSrc
SecondSymbols1.00infobox
SecondUnit oftime1.00infobox
SecondUnit systemSI1.00infobox
Secondis a1-gigahertz microprocessor that has a cycle time of 1 nanosecond0.90text
Secondis amole0.90text
kilosecondsinstance ofThough SI prefixes may also be used to form multiples of the second0.80text
jerkinstance ofis measured in inverse seconds and higher powers of second are involved in derivatives of acceleration0.80text
IT-CsF2instance ofthe best realisation of the second is done with caesium primary standard clocks0.80text
NIST-F2instance ofthe best realisation of the second is done with caesium primary standard clocks0.80text
NPL-CsF2instance ofthe best realisation of the second is done with caesium primary standard clocks0.80text
PTB-CSF2instance ofthe best realisation of the second is done with caesium primary standard clocks0.80text
SUinstance ofthe best realisation of the second is done with caesium primary standard clocks0.80text

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