Mass moment of inertia of a Circle

Calculates the mass moment of inertia of a Circle or a thin circular ring.
`I_z = m*r^2` (about central axis)
`I_x=I_y = 1/2*m*r^2` (about diameter)
Enter 'x' in the field to be calculated.

Rotation axis

Moment of inertia (I)

Mass (m)

Inner radius (r)

Result format

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Here are formulas to calcule the mass moment of inertia of a circle or thin circular ring.

Case of a rotation about the central axis (z-axis on above diagram),
`I_z = m * r^2`

Case of a rotation about a diameter (x-axis or y-axis on above diagram),
`I_x = I_y = 1/2*m * r^2`

m : mass of the circle (kg)
r : circle radius in meter (m)

Mass moment of inertia of a Circle

See also