Search results
Results from the WOW.Com Content Network
Given a flux according to the electromagnetism definition, the corresponding flux density, if that term is used, refers to its derivative along the surface that was integrated. By the Fundamental theorem of calculus , the corresponding flux density is a flux according to the transport definition.
It is used in astronomy to determine the magnitude and spectral class of a star and in meteorology to determine the intensity of the convection in the planetary boundary layer. Radiative flux also acts as a generalization of heat flux, which is equal to the radiative flux when restricted to the infrared spectrum.
Then the horizontal components of flux are considered to cancel each other by symmetry, leaving only the vertical component of the flux as non-zero. In this case [4] some astrophysicists think in terms of the astrophysical flux (density), which they define as the vertical component of the flux (of the above general definition) divided by the ...
The flux to which the jansky refers can be in any form of radiant energy. It was created for and is still most frequently used in reference to electromagnetic energy, especially in the context of radio astronomy. The brightest astronomical radio sources have flux densities of the order of 1–100
In photometry, luminous flux or luminous power [citation needed] is the measure of the perceived power of light. It differs from radiant flux , the measure of the total power of electromagnetic radiation (including infrared , ultraviolet , and visible light), in that luminous flux is adjusted to reflect the varying sensitivity of the human eye ...
Radiant flux: Φ e [nb 2] watt: W = J/s M⋅L 2 ⋅T −3: Radiant energy emitted, reflected, transmitted or received, per unit time. This is sometimes also called "radiant power", and called luminosity in Astronomy. Spectral flux: Φ e,ν [nb 3] watt per hertz: W/Hz: M⋅L 2 ⋅T −2: Radiant flux per unit frequency or wavelength. The latter ...
In astronomy, surface brightness (SB) quantifies the apparent brightness or flux density per unit angular area of a spatially extended object such as a galaxy or nebula, or of the night sky background. An object's surface brightness depends on its surface luminosity density, i.e., its luminosity emitted per unit surface area.
A flow chart describing the relationship of various physical quantities, including radiant flux and exitance. In radiometry, radiant flux or radiant power is the radiant energy emitted, reflected, transmitted, or received per unit time, and spectral flux or spectral power is the radiant flux per unit frequency or wavelength, depending on whether the spectrum is taken as a function of frequency ...