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Hi all, this is my first post. I'm under the gun at the moment because we were just told yesterday to expect a similar problem to the one below on our final, yet we were not taught how to work such a problem in class. (Our teacher does not write the final hence the discrepancy.)

I have a solution manual I am trying to learn how to do this problem with the help of, but it is not going very well. My book only vaguely touches on the inertia tensor so I'm very confused about what's going on in this problem. I've posted the two pages from the solution manual. I keep trying but I can't seem to duplicate the numbers the solution manual gets.

Page 1: http://i43.tinypic.com/2j4d761.jpg

Page 2: http://i41.tinypic.com/w1mhg.jpg

The 'I1' calculation seems to be I

And also for I

If anyone can offer some tips or suggestions on this problem, I would be very grateful. After spending about 4 hours staring at it, googling, etc. I'm really at my wits end.

I have a solution manual I am trying to learn how to do this problem with the help of, but it is not going very well. My book only vaguely touches on the inertia tensor so I'm very confused about what's going on in this problem. I've posted the two pages from the solution manual. I keep trying but I can't seem to duplicate the numbers the solution manual gets.

**1)The problem statement, all variables and equations:**Page 1: http://i43.tinypic.com/2j4d761.jpg

Page 2: http://i41.tinypic.com/w1mhg.jpg

**2) Attempt at solution**The 'I1' calculation seems to be I

_{zz}for a thin plate from the back of my book, where I_{zz}= 1/12*m(a^{2}+ b^{2}). Yet the manual labels that value I1 and seems to use it in place of where I_{xx}should be in the inertia tensor (I_{mat}.) I don't know if this is an error or not.And also for I

_{oa}, I'm using the formula I_{xx}*u_{x}^{2}+ I_{yy}*u_{y}^{2 }+ I_{zz}*u_{z}^{2}where the u's are the unit vectors for r_{o/a}. Since u_{x}is zero, I should get: I_{oa}= I_{yy}*u_{y}^{2 }+ I_{zz}*u_{z}^{2}. Again, I'm unsure of which is I_{yy}and I_{zz}from the solution manual due to the obscure labeling of I1/I2/I3, and I'm unsure of how to identify which is which from the picture. (that's something I never figured out since we are usually given the values)If anyone can offer some tips or suggestions on this problem, I would be very grateful. After spending about 4 hours staring at it, googling, etc. I'm really at my wits end.

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