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!

SHM of cube from an edge

  1. Feb 22, 2015 #1
    1. The problem statement, all variables and given/known data
    We have a cubical hollow box, edge length ##a## suspended horizontally from a frictionless hinge along one of its edges. The box is displaced slightly and undergoes SHM. Show that the period of the oscillation is given by ## T = 2\pi \sqrt{\frac{7\sqrt{2}a}{9g}} ##
    2. Relevant equations


    3. The attempt at a solution

    ##E_{tot} = \frac{1}{2}I\omega^2 + mg\left(\frac{\sqrt{2}}{2a}\cos\theta\right) ##Then apply taylor expansion and differentiate to get: ## \ddot\theta = \frac{mga}{\sqrt{2}I} \theta ## and using ##I = \frac{2}{3}ma^2## gives ##T = 2\pi \sqrt{\frac{2\sqrt{2}a}{3g}}##

    Help is much appreciated
     
    Last edited: Feb 22, 2015
  2. jcsd
  3. Feb 22, 2015 #2
    Ah, turns out the moment of inertia was incorrect.....
     
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook

Have something to add?
Draft saved Draft deleted