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Question: What is the unit of measure for Moment of Inertia under Mass Properties in the English system?

I am also puzzled by this: the same model gives different Radius of Gyration in K4 and CKD19. I am running both, position my CG at the origin, getting the same mass, CG etc. but different RoG. Which one is correct?

Thanks

I just did a quick check and compared CK19.01 to KC4.0.2.

I created a 1"Ø rod 100" long centered at the origin.

For KC4.0.2

Rx=28.8685959728, Ry=28.8685959703, Rz=.353553493763

For CK19.01

Rx=28.868596, Ry=28.868596, Rz=.35355339

The only difference I got was in the 6th digit of the Rz values.  The others were different becasue CK 19.01 truncates to 6 decimal places.  If I had to guess, I would think that this is a rounding error of some sort.

Outside of school, I've never met anyone that actually that actually had a use for the Radius of Gyration since it relates to the rotaional inertia of an object about an axis.   Do you use this value in your work?  Just curious ...

Jay