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ppy
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I know the radiative flux traveling through the atmosphere of a star obeys the equation:
dF/dr=-opacity*F*density
If we have an isothermal atmosphere the density decreases with radius such that density is proportional to 1/r^2.
If the flux entering such an atmosphere from the core of the star at radius r0 is F0 show that the flux that reaches radius r is
F(r)=F0 *e^opacity*(r^-2 -r0^-2) where the opacity is a constant.
I do not understand I'm guessing I need to integrate the 1st order ODE but how can I do this when flux is on both sides of the equation and where does the exponential come from in the answer?
Help!
Thanks :) Note: for some reason the symbols tab is not working on my laptop
dF/dr=-opacity*F*density
If we have an isothermal atmosphere the density decreases with radius such that density is proportional to 1/r^2.
If the flux entering such an atmosphere from the core of the star at radius r0 is F0 show that the flux that reaches radius r is
F(r)=F0 *e^opacity*(r^-2 -r0^-2) where the opacity is a constant.
I do not understand I'm guessing I need to integrate the 1st order ODE but how can I do this when flux is on both sides of the equation and where does the exponential come from in the answer?
Help!
Thanks :) Note: for some reason the symbols tab is not working on my laptop