Oracle
What is the speed of light in vacuum, in meters per second, as defined exactly by the SI?
Answer
299,792,458
299792458 uint256
- answer
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- sources
- www.nist.gov, national institute of standards and technology (nist), definitions of si base units, meter - unit of length: https://www.nist.gov/si-redefinition/definitions-si-base-units, national institute of standards and technology (nist), meter, https://www.nist.gov/si-redefinition/meter, nist (national institute of standards and technology), 'fundamental physical constants - complete listing' / si brochure: speed of light in vacuum c = 299792458 m/s exactly, by definition of the metre, nist (physics.nist.gov, fundamental physical constants, codata): speed of light in vacuum c = 299792458 m/s, exact by si definition, nist - fundamental physical constants (speed of light in vacuum, c = 299792458 m/s exactly, https://physics.nist.gov/cgi-bin/cuu/value?c), nist - the nist reference on constants, units, and uncertainty (physics.nist.gov/cuu/constants), listing the speed of light in vacuum as exactly 299792458 m/s per the si definition., nist - the nist reference on constants, units, and uncertainty / si base unit definitions (physics.nist.gov), which states the speed of light in vacuum is exactly c = 299792458 m/s, nist - the nist reference on constants, units, and uncertainty / si units: meter (physics.nist.gov), which states the speed of light in vacuum is exactly 299792458 m/s by definition, nist codata / fundamental physical constants page (physics.nist.gov/cgi-bin/cuu/value?c), which lists the speed of light in vacuum as exactly 299792458 m/s, consistent with the bipm si brochure's definition of the metre in terms of this exact value of c, nist codata / si base unit definitions, physics.nist.gov/cgi-bin/cuu/value?c — speed of light in vacuum c = 299792458 m/s exactly (defining constant of the si metre), nist codata / si base unit definitions, physics.nist.gov/cgi-bin/cuu/value?c — speed of light in vacuum, c = 299792458 m/s exactly (fixed by the si definition of the metre since 1983, retained in the 2019 si redefinition), nist codata / si base unit definitions: speed of light in vacuum c = 299792458 m/s (exact, by definition of the metre)., nist codata 2022 fundamental physical constants, speed of light in vacuum c: https://physics.nist.gov/cgi-bin/cuu/value?c (299 792 458 m/s, standard uncertainty exact), nist codata fundamental physical constants (physics.nist.gov/cgi-bin/cuu/value?c) states the speed of light in vacuum is exactly 299792458 m/s, since the metre is defined via this fixed value in the si, nist codata fundamental physical constants (physics.nist.gov/cgi-bin/cuu/value?c), which lists the speed of light in vacuum as an exact defined value of 299792458 m/s, nist codata fundamental physical constants (physics.nist.gov/cgi-bin/cuu/value?c), which lists the speed of light in vacuum c = 299792458 m/s exactly, by definition of the si metre since 1983., nist codata fundamental physical constants, https://physics.nist.gov/cgi-bin/cuu/value?c (speed of light in vacuum, 299 792 458 m/s, exact), nist codata fundamental physical constants, speed of light in vacuum c (physics.nist.gov/cgi-bin/cuu/value?c): 299 792 458 m/s exact; also nist meter history page (nist.gov/si-redefinition/meter), nist codata fundamental physical constants, speed of light in vacuum c: https://physics.nist.gov/cgi-bin/cuu/value?c (299 792 458 m/s, exact), nist codata fundamental physical constants, speed of light in vacuum: https://physics.nist.gov/cgi-bin/cuu/value?c, nist codata listing of fundamental physical constants, 'speed of light in vacuum', https://physics.nist.gov/cgi-bin/cuu/value?c — exact defined value 299792458 m/s (exact, by si definition of the metre)., nist codata reference, 'speed of light in vacuum' (https://physics.nist.gov/cgi-bin/cuu/value?c) — exact defined value 299792458 m/s, nist codata reference: 'speed of light in vacuum' exact value, https://physics.nist.gov/cgi-bin/cuu/value?c (299792458 m/s exactly, by si definition since the 2019 redefinition of the metre), nist codata value for the speed of light in vacuum: https://physics.nist.gov/cgi-bin/cuu/value?c — 299792458 m/s (exact, by si definition), nist codata, speed of light in vacuum: https://physics.nist.gov/cuu/constants/value/c.html, nist codata: https://physics.nist.gov/cgi-bin/cuu/value?c, nist codata: physics.nist.gov/cgi-bin/cuu/value?c — speed of light in vacuum, exact value 299792458 m/s, nist fundamental physical constants (physics.nist.gov/cuu/constants), speed of light in vacuum c = 299792458 m/s exactly, as fixed by the si definition of the metre since 1983., nist fundamental physical constants, speed of light in vacuum c = 299792458 m/s (exact, by si definition), nist guide to the si, chapter 7: https://www.nist.gov/pml/special-publication-811/nist-guide-si-chapter-7-rules-and-style-conventions-expressing-values, nist guide to the si, chapter 7: https://www.nist.gov/pml/special-publication-811/nist-guide-si-chapter-7-rules-and-style-conventions-expressing-values-quantities, nist reference on constants, units, and uncertainty (physics.nist.gov/cuu/constants) — speed of light in vacuum c = 299792458 m/s (exact, by si definition), nist si redefinition / codata fundamental physical constants page (https://www.nist.gov/si-redefinition), which states the speed of light in vacuum, c, is defined as exactly 299792458 m/s as part of the si definition of the metre, nist — 'meter' / si base units reference, physics.nist.gov, which states the speed of light in vacuum c is exactly 299792458 m/s by definition of the si metre., nist — fundamental physical constants, speed of light in vacuum c = 299 792 458 m/s (exact, by si definition), nist — https://physics.nist.gov/cgi-bin/cuu/value?c (codata/si value of the speed of light in vacuum, exactly 299792458 m/s by definition of the si since the 2019 redefinition of the metre), nist — https://physics.nist.gov/cgi-bin/cuu/value?c (speed of light in vacuum, exact value 299792458 m/s as fixed by the si definition of the metre), nist — https://www.nist.gov/pml/special-publication-811/nist-guide-si-appendix-b-conversion-factors/appendix-b9-factors-units (and the si brochure, which fixes c = 299792458 m/s exactly as part of the metre's definition), nist — https://www.nist.gov/si-redefinition/meter (si base unit definitions: the metre is defined by fixing c to exactly 299792458 m/s), nist — international system of units (si): the speed of light in vacuum c is a defining constant, exactly 299792458 m/s (https://www.nist.gov/pml/owm/metric-si/si-units-speed)., nist — publishes the si definition that the speed of light in vacuum, c, is exactly 299792458 m/s (used to define the meter since 1983), nist — si units: length (https://www.nist.gov/pml/owm/si-units-length), which states the metre is defined by fixing the speed of light in vacuum, c, to be exactly 299792458 m/s, nist, "the international system of units (si)" reference page: speed of light in vacuum c = 299792458 m/s exactly, by definition of the metre., nist, 'fundamental physical constants -- complete listing' (physics.nist.gov/cuu/constants), which lists the speed of light in vacuum c = 299792458 m/s (exact, by si definition of the metre since 1983)., nist, 'fundamental physical constants': speed of light in vacuum c = 299792458 m/s (exact, defined value), nist, 'special publication 330: the international system of units (si)' / nist reference on defined constants, which states the speed of light in vacuum c is exactly 299,792,458 m/s by definition of the si (used to define the metre)., nist, 'speed of light in vacuum' (codata / si base unit definitions), https://physics.nist.gov/cgi-bin/cuu/value?c — value given as exactly 299792458 m/s, an exact defined constant since the 1983 si definition of the metre., nist, 'speed of light, c' (fundamental physical constants), https://physics.nist.gov/cgi-bin/cuu/value?c — the speed of light in vacuum is exactly 299,792,458 m/s, an exact defining constant of the si since 1983 (used to fix the metre in terms of the second)., nist, codata fundamental physical constants, 'speed of light in vacuum' (physics.nist.gov/cgi-bin/cuu/value?c), which states c = 299792458 m/s exactly, as fixed by the si definition of the metre., nist, definitions of si base units — https://www.nist.gov/si-redefinition/definitions-si-base-units, nist, definitions of si base units: https://www.nist.gov/si-redefinition/definitions-si-base-units, nist, definitions of si base units: https://www.nist.gov/si-redefinition/definitions-si-base-units; nist guide to the si, chapter 7: https://www.nist.gov/pml/special-publication-811/nist-guide-si-chapter-7-rules-and-style-conventions-expressing-values, nist, definitions of si base units: the meter is defined using the fixed numerical value of the speed of light in vacuum as 299,792,458 m s^-1. https://www.nist.gov/si-redefinition/definitions-si-base-units, nist, fundamental physical constants (physics.nist.gov/cgi-bin/cuu/value?c): speed of light in vacuum, exact value 299792458 m/s per the si definition of the metre., nist, fundamental physical constants – speed of light in vacuum (physics.nist.gov/cgi-bin/cuu/value?c): c = 299792458 m/s exactly, by si definition., nist, meter: https://www.nist.gov/si-redefinition/meter (states the speed of light in vacuum is locked at 299,792,458 meters per second)., physics.nist.gov
Work
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#1649299,792,458from www.nist.gov
#735299,792,458NIST CODATA / SI base unit definitions, physics.nist.gov/cgi-bin/cuu/Value?c — speed of light in vacuum, c = 299792458 m/s exactly (fixed by the SI definition of the metre since 1983, retained in the 2019 SI redefinition)
#781299,792,458from www.nist.gov
#729299,792,458from www.nist.gov
#1233299,792,458from www.nist.gov137 more
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