Help with a simple exercise in astrophysics.

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The discussion revolves around a student seeking help with an astrophysics exercise involving the calculation of Cbol using the given equation for bolometric magnitude. The student is unsure how to proceed due to a lack of information on solar luminosity and temperature. Other forum members suggest that the student should demonstrate their understanding by attempting to solve the problem first. It is highlighted that relevant values, such as solar luminosity, can typically be found in textbooks, which the student later acknowledges. The conversation emphasizes the importance of utilizing available resources and showing effort in problem-solving.
Xalkias
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So i began studying on my own for my astrophycis class that will start on 2 weeks and i have trouble solving an exercise. So the exercise goes as follows: given that mbol=-2.5log(∫fλdλ)+Cbol and mbol=-26.83 for sun. Show that Cbol=-18.99 . I'm stuck and i can't find any hint from the book that I am studying.
Please help. Thanks
 
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first of all, I think you should post your question as a homework problem here.
secondly, before we are allowed to help you, you should show some effort on your side, maybe an attempt to solve the problem, so we can see where exactly is the blocking point.
Which part is not clear to you? What equations related to the apparent magnitude are available to you?
 
I'm sorry I'm new to this forum.
Ok so In my mind I have to find f and then solve for C. So for the sun : ∫fdλ= L/4πd^2 (d=1AU) but then L is unknown so I can't calculate F. Temperature is not given so I can't use that either to calculate F. What should I do
 
Xalkias said:
I'm sorry I'm new to this forum.
Ok so I know for the sun : ∫fdλ= L/4πd^2 (d=1AU) but then L is unknown so I can't calculate F. Temperature is not given so I can't use that either to calculate F.

Great, you actually know the solution :) I think in many astrophysics problems like this one, you won't be given Solar luminosity or irradiance each time in the problem definition. I am pretty sure you can find at least one of these values in your book. Can you?
 
Ohh Yes there is a lists of all luminosities in the book but I thought they would mention if this lists was needed.
Thank you for your time.
 
The book claims the answer is that all the magnitudes are the same because "the gravitational force on the penguin is the same". I'm having trouble understanding this. I thought the buoyant force was equal to the weight of the fluid displaced. Weight depends on mass which depends on density. Therefore, due to the differing densities the buoyant force will be different in each case? Is this incorrect?

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