Help calulating the monent of inertia

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To calculate the moment of inertia for a structure made of three identical thin rods, each of length L and mass M, the appropriate formulas are Icm = 1/12 ML^2 and I = 1/3 ML^2. The moment of inertia for Rod C, which is aligned with the axis of rotation, is determined to be 1/3 ML^2. For Rod A, the moment of inertia must consider the varying distances of its particles from the axis. The Parallel Axis Theorem is necessary for calculating the moment of inertia for Rod B. The discussion concludes with the participant confirming their understanding of the calculations.
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three identical thin rods each of length L and massM are welded perpendicluar to one another determine the monemt of inertia of the structure pink line is the axis of rotation. i think i need to use Icm= 1/12 ML^2 and I=1/3ML^2
but not sure which rod uses which formula
 

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If the pink line is passing through the end of C then the MI for Rod C is 1/3ML^2.

For MI of A, think of the distance of different particles of the rod A from the axis.

For MI of B you have to use Parallel axis theorem. Go through it.

MP
 
thanks i got it now
 

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