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Section 7-33 entries

7-3.1radiant energy density 7-3.2spectral radiant energy density in terms of wavelength 7-3.3spectral radiant energy density in terms of wavenumber

7-3.2

spectral radiant energy density in terms of wavelength

URNurn:iso:std:iso:80000:-7:ed-2:en:item:7-3.2

Download RDF.jsonld .ttl

https://metanorma.github.io/isq-smart/quantities/part-7/t7-3.2
urn:iso:std:iso:80000:-7:ed-2:en:item:7-3.2

ISQ Identifiers

ISO

urn:iso:std:iso:80000:-7:ed-2:en:item:7-3.2

IEC

urn:iec:std:iec:80000-7:2019:::item:7-3.2

Designations

ENspectral radiant energy density in terms of wavelength

FRénergie rayonnante spectrique volumique en longueur d'onde

Symbol

w_{λ}

Notation systems

Rendered

w_{λ}

AsciiMath

w_lambda

LaTeX

w_{\lambda}

Definition

change of radiant energy density with wavelength, expressed by

w_{λ} = \frac{d w}{d λ}

where $w$ is radiant energy density (radiant energy density) as a function of wavelength $λ$ (ISO 80000-3: Space and time)

variation de l'énergie rayonnante volumique en fonction de la longueur d'onde, exprimée par

w_{λ} = \frac{d w}{d λ}

où $w$ est l'énergie rayonnante volumique (radiant energy density) en fonction de la longueur d'onde $λ$ (ISO 80000-3: Space and time)

Units

\frac{J}{m^{3} \cdot n m}

joule per cubic metre nanometre

View related quantities →

k g \cdot m^{- 2} \cdot s^{- 2}

kilogram per square metre second squared

View related quantities →

Notes

Spectral radiant energy density within a Planckian radiator is given by $w_{λ} = 8 π h c_{0} \cdot f (λ, T)$ , where $h$ is the Planck constant (ISO 80000-1), $c_{0}$ is speed of light in vacuum (ISO 80000-1), $T$ is thermodynamic temperature (<) and

f (λ, T) = \frac{λ^{- 5}}{exp (c_{2} λ^{- 1} T^{- 1}) - 1}

For the radiation constant $c_{2}$ in $f (λ, T)$ , see ISO 80000-1.

L'énergie rayonnante spectrique volumique d'un radiateur de Planck est donnée par $w_{λ} = 8 π h c_{0} \cdot f (λ, T)$ , où $h$ est la constante de Planck (ISO 80000-1), $c_{0}$ est la vitesse de la lumière dans le vide (ISO 80000-1), $T$ est la température thermodynamique (ISO 80000-5: Thermodynamics) et

f (λ, T) = \frac{λ^{- 5}}{exp (c_{2} λ^{- 1} T^{- 1}) - 1}

Pour la constante de rayonnement $c_{2}$ dans $f (λ, T)$ , voir l'ISO 80000-1.

Concept HierarchyPendrill (2024)

1dimensionless quantitiesLevel 0 · Kind

Broader concepts

◇ dimensionless quantities

Ontology
isq:Quantity smart:TermEntry

Class Hierarchy

smart:Entity smart:TermEntryisq:Quantity

A physical quantity as defined in ISO/IEC 80000, with associated symbols, definitions, and units of measurement.

Instance IRI

isq:t7-3.2

Properties

isq:QuantityShape

Property	Value
rdf:type	isq:Quantity smart:TermEntry
dcterms:identifier	7-3.2
skosxl:prefLabel	"spectral radiant energy density in terms of wavelength"@en
skosxl:altLabel	"w_lambda"@en
skos:definition	change of radiant energy density with wavelength, expressed by [stem%unnumbered] ++++ w_lambda = ("d"w)/("d"lambda) +++…
skos:note	Spectral radiant energy density within a Planckian radiator is given by stem:[w_lambda = 8 pi h c_0 * f(lambda, T)], whe…
isq:hasUnit	J/(m^3nm) (joule per cubic metre nanometre)kgm^(-2)*s^(-2) (kilogram per square metre second squared)
isq:hasDimension	isq:Dimension
smart:hasBindingnessType	bindingness-type:normative
dcterms:isPartOf	isq:part-7

Related Entities

isq:QuantityShape isq:part-7 isq:Unit isq:Dimension isq:hasDimension smart:TermEntry