# Specific Intensity, Flux, Flux Density, Radiative Transfer

• zeegoat
In summary, specific intensity is a measure of the amount of radiant energy per unit time, per unit solid angle, per unit frequency or wavelength, per unit area, and per unit solid angle in the direction of propagation. It is also known as brightness or radiance. Flux is a measure of the amount of radiant energy passing through a given area per unit time, while flux density is a measure of the amount of radiant energy per unit frequency or wavelength, per unit area, and per unit solid angle in the direction of propagation. Radiative transfer is the process by which energy is transferred through a medium by electromagnetic radiation, and it involves absorption, emission, and scattering of radiation by particles in the medium. These concepts are all important in understanding the
zeegoat
Hi, I'm new to the technical aspects of astronomy and I'm having trouble quantifying what the definitions of some of these terms are. I can find equations that relate most of them, but I'm not sure how to use any of them.

The terms are specific intensity, flux, flux density, and monochromatic specific intensity. I've tried searching for websites that relate to these terms but so far I'm out of luck.

Any help is greatly appreciated.

## What is specific intensity?

Specific intensity is a measure of the amount of radiant energy per unit time, per unit solid angle, per unit frequency or wavelength, per unit area, and per unit solid angle in the direction of propagation. It is also known as brightness or radiance.

## What is flux?

Flux is a measure of the amount of radiant energy passing through a given area per unit time. It is the rate of energy flow and is commonly used to describe the amount of energy emitted or received by an object.

## What is flux density?

Flux density is a measure of the amount of radiant energy per unit frequency or wavelength, per unit area, and per unit solid angle in the direction of propagation. It is also known as spectral flux or spectral radiance.

Radiative transfer is the process by which energy is transferred through a medium by electromagnetic radiation. It involves the absorption, emission, and scattering of radiation by particles in the medium, and is important in understanding the flow of energy in various physical systems.

## How are specific intensity, flux, flux density, and radiative transfer related?

Specific intensity, flux, and flux density are all measures of radiant energy, but they differ in the units and dimensions they use. Radiative transfer is the process that governs the transfer of this energy through a medium. All of these concepts are important in understanding the behavior and properties of electromagnetic radiation in various systems, from the smallest subatomic particles to the vast reaches of space.

• Electromagnetism
Replies
28
Views
2K
• Introductory Physics Homework Help
Replies
35
Views
3K
• Electromagnetism
Replies
43
Views
2K
• Astronomy and Astrophysics
Replies
1
Views
1K
• Electromagnetism
Replies
2
Views
3K
• Electromagnetism
Replies
1
Views
1K
• Astronomy and Astrophysics
Replies
21
Views
1K
• Materials and Chemical Engineering
Replies
2
Views
3K
• Classical Physics
Replies
1
Views
1K
• Science and Math Textbooks
Replies
7
Views
2K