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[SOLVED] a tricky Moment of Inertia question, help needed...
The question is in the JPG attachment.
This is what i tried:
Obviously the side which is right on the axis has no moment of inertia so we're left with the 2 horizontal ones and the other vertical. for the two horizontal sides we've got an equation: (M*L^2)/3 and we consider it twice.
the last side is probably where i went wrong  i thought it's simply M*L^2 because it can be regarded as a point mass at distance L but that didn't work. then i tried using the parallel axis theorem but that didn't help too.
Any thoughts? i'm sure its really easy for most of you guys...
Thanx.
The question is in the JPG attachment.
This is what i tried:
Obviously the side which is right on the axis has no moment of inertia so we're left with the 2 horizontal ones and the other vertical. for the two horizontal sides we've got an equation: (M*L^2)/3 and we consider it twice.
the last side is probably where i went wrong  i thought it's simply M*L^2 because it can be regarded as a point mass at distance L but that didn't work. then i tried using the parallel axis theorem but that didn't help too.
Any thoughts? i'm sure its really easy for most of you guys...
Thanx.
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