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!

Moment of Inertia

  1. Feb 20, 2005 #1
    I was wondering how to start a. If I can get (a) I am pretty sure I can get b and c with not too much trouble


    I am really lost to how to even start this problem
  2. jcsd
  3. Feb 20, 2005 #2
    You did to do an integral over the volume [itex] \int \,dm*r^2 \,dv [/itex] where [itex]\,dm[/itex] is just the density of the material. The easiest way to do this I think would be to only do the above integral for one of the 4 quadrates and then times that answer by 4. r for one axes would be x and for the other would be y.
  4. Feb 20, 2005 #3
    Ok I think I found the answer

    for Moment of Inertia for

    [tex] x= \frac{mab^3}{3} [/tex]

    [tex] y= \frac{ma^3b}{4} [/tex]

    Could someone show me how to derive these though??
    Last edited: Feb 20, 2005
  5. Feb 20, 2005 #4


    User Avatar
    Science Advisor
    Homework Helper

    How did u find those results...?

  6. Feb 20, 2005 #5
    A website... I don't have the url anymore... why is it incorrect?
  7. Feb 20, 2005 #6


    User Avatar
    Science Advisor
    Homework Helper

    So they only gave the results and not how to get them,huh...?It looks weird,because one may expect the same denominator for both.

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

Have something to add?

Similar Discussions: Moment of Inertia
  1. Moment of Inertia? (Replies: 9)