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: Radius of Gyration

  1. Jan 14, 2005 #1
    Hi. I'm having trouble knowing where to start on a problem. Basically, I have to find the radius of gyration of this diamond shape, about an axis through its centre and perpendicular to the plane. All sides are 0.5m in length and from tip to tip horizontally it measures 0.8m. I'm not quite sure how to go about this. Any help would be appreciated.

    Attached Files:

  2. jcsd
  3. Jan 14, 2005 #2
    You could calculate the moment of inertia from it's definition: [tex]I=\int r^2 dm[/tex] with [tex]r^2=x^2+y^2[/tex] and [tex]dm=\rho dxdy[/tex]. Then you will have to use functions describing the shape in your integral limits. Or you can use the perpendicular axis theorem (http://hyperphysics.phy-astr.gsu.edu/hbase/perpx.html)
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook