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!

G within a thin disk

  1. Aug 4, 2013 #1
    I'm researching dark matter and how it affects galaxy rotation curves, I came up with the problem below.

    Imagine a very thin, flat disk which has uniform mass per unit area.

    What is the gravitational field strength (g) within the disk itself? How does g vary with respect to r, the distance from the center of the disk.

    The area density of the disk is δ and the radius of the disk is R.
  2. jcsd
  3. Aug 5, 2013 #2


    User Avatar
    Science Advisor

  4. Aug 5, 2013 #3

    Most of the threads focus on the z-axis. But in order for me to simulate a galaxy, I have to focus on the x-axis.

    I came up with an integral to find the value of g, but its value ends up being infinite.

    I can write it down step-by-step to let you guys find out where I went wrong.
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook