# Monochromatic flux expression?

• jeebs
In summary, the conversation discusses how to derive an expression for converting between monochromatic flux expressed in wavelength and frequency units. The formula for finding the monochromatic flux of a star is F(Δf) = ΔE / ΔtΔfΔA and F(Δλ) = ΔE / ΔtΔλΔA, where E represents energy, t represents time, Δf represents frequency bandwidth, A represents the area of photon collecting surface, and Δλ represents wavelength bandwidth. The speaker had previously learned how to do this question but cannot remember how to do it now. They mention that it may involve differentiation or integration. They request an explanation for the answer as they are more interested in
jeebs
hi, I am having trouble deriving an expression for converting between monochromatic flux expressed in wavelength and in frequency units.

i think that the monochromatic flux of a star is found by

F(Δf) = ΔE / ΔtΔfΔA

F(Δλ) = ΔE / ΔtΔλΔA

where
E = energy,
t = time,
Δf = frequency bandwidth,
A = area of photon collecting surface, and
Δλ = wavelength bandwidth.

i was shown how to do this question by my tutor but i can't remember how to do it, it involved differentiation or integration i think...

thanks!

oh, and if you take the time to answer, could you please give me an explanation, as the answer itself doesn't really teach me anything, I'm more interested in how you found that answer.

I think you should be posting this in the homework section.

## 1. What is monochromatic flux expression?

The monochromatic flux expression is a mathematical equation used to describe the amount of light or energy emitted by a source at a specific wavelength. It takes into account the intensity, distance, and area of the source, as well as the wavelength of the light.

## 2. How is monochromatic flux expression calculated?

The monochromatic flux expression is calculated by multiplying the intensity of the source by the surface area of the source and dividing by the square of the distance from the source. This is then multiplied by the wavelength of the light in question.

## 3. What is the unit of measurement for monochromatic flux expression?

The unit of measurement for monochromatic flux expression is watts per square meter per nanometer (W/m²/nm). This unit represents the amount of energy emitted by a source at a specific wavelength per unit of area.

## 4. How is monochromatic flux expression used in scientific research?

Monochromatic flux expression is commonly used in various fields of science, such as astronomy, spectroscopy, and photometry, to measure and analyze the intensity of light emitted by different sources. It is also used to calculate the flux density of electromagnetic radiation and to determine the properties of different objects in space.

## 5. What factors can affect the monochromatic flux expression?

The monochromatic flux expression can be affected by several factors, including the distance from the source, the surface area of the source, and the wavelength of the light being emitted. Other factors such as atmospheric conditions, absorption by particles, and the temperature of the source can also impact the monochromatic flux expression.

• Astronomy and Astrophysics
Replies
3
Views
1K
• Astronomy and Astrophysics
Replies
5
Views
1K
• Introductory Physics Homework Help
Replies
1
Views
2K
• Astronomy and Astrophysics
Replies
3
Views
850
• Astronomy and Astrophysics
Replies
8
Views
2K
• Introductory Physics Homework Help
Replies
2
Views
3K
• Astronomy and Astrophysics
Replies
2
Views
2K
• Electromagnetism
Replies
28
Views
2K
• Introductory Physics Homework Help
Replies
2
Views
557
• Electromagnetism
Replies
2
Views
2K