Symmetric object prove principle axis goes through CM

m0nk3y
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Homework Statement


c) For such a "symmetric" object, prove that any axis going through the center of mass is a principal axis.


Homework Equations


mimg276.gif



The Attempt at a Solution



I am not sure how they want me to prove this. I was looking at the Displacement Axis Thm but I am not sure how to use it, or appropriate for this problem.

Thanks in advance.
 
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The tensor of inertial you have is a sum of that for a stick and that for a disk.
Each of these has all principal axes through the center.
 
Thank you for your reply,

Is there a way to prove this with math?
 
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