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!

Gravitationtrouble setting up equation

  1. Oct 1, 2007 #1
    My problem lies in setting this up.

    A particle of mass M is split into two pieces, M and M-m, and are set some distance apart.

    What ratio of m/M maximizes the magnitude of the gravitational attraction.

    I will definately be needing [tex] F_g=\frac{Gm_1m_2}{r^2}[/tex]

    I know that after making appropriate substitutions I get.

    but my problem is in how to compare what happens as m-->M?

    Any thoughts in the set up?

  2. jcsd
  3. Oct 1, 2007 #2


    User Avatar
    Science Advisor
    Homework Helper
    Gold Member

    You mean that the pieces are m and M-m!!
    basically, you have to optimize the product m(M-m) as a function of m. Just take the derivative with respect to m and set the derivative equal to zero. That will give you the optimum m and then you may calculate the ratio m/M.
    Last edited: Oct 1, 2007
  4. Oct 1, 2007 #3
    AWWWW!! I knew that! I wrote out the product wrong! Thanks nrqed

Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook

Have something to add?

Similar Discussions: Gravitationtrouble setting up equation