1. Not finding help here? Sign up for a free 30min 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!

Gravitational Potential Energy of Envelope around star

  1. Sep 20, 2009 #1
    I am confused about this question:

    A giant star has a radius of 200 Rsun, with core of mass 0.6 Msun surrounded by an extended envelope of mass 0.2 Msun.
    (a) Estimate the gravitational potential energy of the envelope.



    When it says the envelope, does this mean the 'shell' surrounding the interior, where you can use the conservation of mass equation of a shell => dm/dr = 4pi*p*r^2 and Plugging it into Gravitational potential energy equation: dU = -[G M(r)*dm]dr/r. In this case dm is the mass of envelope and M(r) is 0.6Msun and r would be 200Rsun. Not sure what dr would be, since it is the thickness of the envelope. Thanks
     
  2. jcsd
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook

Can you offer guidance or do you also need help?



Similar Discussions: Gravitational Potential Energy of Envelope around star
  1. Potential Energy (Replies: 0)

Loading...