Moment of Inertia Problem: Perpendicular Axes THM

Join the discussion
Registration is free. Start your own thread to ask a follow-up.
1 reply · 5K views
ultimateceej
Messages
6
Reaction score
0
[SOLVED] Moment of Inertia Problem: Perpendicular Axes THM

Homework Statement


First, the problem asked us to basically prove the Perp. Axes Thm and then use it to prove that the MoI of a thin, uniform square sheet with mass M and side L through ANY axis in its plane is equal to 1/2 M L^2



Homework Equations


The moment of inertia for a square sheet of a perpendicular axis through its center of mass is 1/6 M L^2


The Attempt at a Solution



First, I tried to simply say that I_x is perp. to I_y and that their sum is I_o which is equal to 1/6 M L^2 (above). And since the square is uniform, I_x = I_y = 1/2 I_o but this gave me I_x = 1/12 M L^2. Is it possible that the book has a misprint? How is it possible for the moments of inertia of an axis in the plane to be 3 times the MoI through the center of mass?
 
Physics news on Phys.org
Nevermind, physics teacher confirms the the typo. The correct answer is what I got, I_x = 1/12 M L^2