1. Limited time only! Sign up for a free 30min personal tutor trial with Chegg Tutors
    Dismiss Notice
Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Homework Help: Eddington luminosity for star made out of protons

  1. Mar 30, 2010 #1
    Imagine that a star could be composed entirely of protons so that Thomson scattering by protons dominated the stellar opacity. How luminous, in [tex]L_{\odot}[/tex], would the star have to be to blow itself apart by radiation pressure?

    I know that the luminosity has to be greater than the eddington luminosity so that radiation pressure is greater that gravity.

    The equation I have for scattering for protons is [tex] \sigma_{T} = \frac{1*C^2}{6\pi}* (\frac{p^2}{(m_{p} * c^2)})^2[/tex]

    This gives me [tex]3.90 * 10^{-35} meters^2[/tex]

    The eddington luminosity equation is then [tex] L = \frac{4\pi*G*(m_{p}*C*mass of star)}{\sigma_{T}} [/tex]

    The problem is that I wasn't given a mass or radius for the star, so I'm stuck.
     
    Last edited: Mar 30, 2010
  2. jcsd
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook

Can you offer guidance or do you also need help?
Draft saved Draft deleted