- #1
jmm5872
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A light source has uniform intensity I(with respect to wavelength) within a
circle of diameter 3 arcmin on the sky. The flux of radiation reaching the observer is
10^(−16) erg cm^(−2) s^(−1). Calculate the intensity of the light from this source.
Relevent Equations:
This is where my confusion comes in, I'm not really sure what the relavant equations are. The only equation I have found in the textbook is this:
F = Integral (d[tex]\omega[/tex])cos[tex]\theta[/tex]
(I can't seem to get the latex to work correctly, I hope this makes sense as is).
I also know flux is watts per unit area, but I'm new to this on the astronomy side. I also know an erg is 10^-7 Ws. How would I use the 3 arcmin, would I find the area of a circle with 1.5 arcmin radius? Don't you need the distance to be able to calculate the flux? Any hints to get started would be great.
circle of diameter 3 arcmin on the sky. The flux of radiation reaching the observer is
10^(−16) erg cm^(−2) s^(−1). Calculate the intensity of the light from this source.
Relevent Equations:
This is where my confusion comes in, I'm not really sure what the relavant equations are. The only equation I have found in the textbook is this:
F = Integral (d[tex]\omega[/tex])cos[tex]\theta[/tex]
(I can't seem to get the latex to work correctly, I hope this makes sense as is).
I also know flux is watts per unit area, but I'm new to this on the astronomy side. I also know an erg is 10^-7 Ws. How would I use the 3 arcmin, would I find the area of a circle with 1.5 arcmin radius? Don't you need the distance to be able to calculate the flux? Any hints to get started would be great.