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# Moment of Inertia Calculations

abinand_palanisamy
Member Posts:

**4**EDU
Hi everyone, I'm new to OnShape, and I have some questions on how the moment of inertia is calculated. My dimensions for this cube is 10 cm for each side length, with a diameter of 8 cm semi-sphere cut out of the top face of the cube. For example, as seen in the image, the moment of inertia along the X-axis is 84.61. Im extremely confused on how this calculation was made, as I thought the formula for moment of inertia was [(Distance from center of mass)^2] * Mass. Wouldn't this give (5^2) * 5.1546029? Is the error within my formula for the moment of inertia?

0

## Comments

476PRO209PROOnshape takes the moment of inertia

about the center of mass. So, also as said above, it's easy to verifiy this using simple shapes like cubes, spheres, and cylinders. The center of mass of those is easy. For your shape, it will take a few steps.2734EDU