Compute Ratio for Luminosity to Mass: Compare to Sun

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The discussion focuses on calculating the luminosity-to-mass ratio for a star, with the user determining a mass of 1 solar mass (Msun) and a luminosity of 1000 solar luminosities (Lsun). The computed ratio is confirmed to be 1000 Lsun/Msun, which is compared to the Sun's ratio. Additionally, the user inquires about estimating the lifespan of very luminous stars as red giants, with a response indicating a maximum duration of approximately 10 million years. The conversation highlights the relationship between stellar luminosity, mass, and lifespan in astrophysics.
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Hi hi hi,

So guys I'm just having a little trouble with this question..

Compute the ratio between the luminosity from part B to the mass from part A. How does that ratio compare with the Sun's ratio of luminosity to mass?

So for part A I got 1Msun and part B I got 1000Lsun

So to compute the ratio I was just wondering I divide Luminosity/ Mass and isn't it just 1000 then? :oEdit: Also how do I estimate the maximum amount of time these very luminous stars can last as red giants from your answer to part C (the question above).
 
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oldspice1212 said:
Hi hi hi,

So guys I'm just having a little trouble with this question..

Compute the ratio between the luminosity from part B to the mass from part A. How does that ratio compare with the Sun's ratio of luminosity to mass?

So for part A I got 1Msun and part B I got 1000Lsun

So to compute the ratio I was just wondering I divide Luminosity/ Mass and isn't it just 1000 then? :o
Yes, the ratio is 1000 LSun/MSun .


Edit: Also how do I estimate the maximum amount of time these very luminous stars can last as red giants from your answer to part C (the question above).
This is an entirely different question.
 
Thanks yeah I noticed that its the only information I had besides I didn't mention the H R diagram. XD sorry about that.I got 10^7 years if anyone is interested for that question.
 
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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