# Moment of Inertia - Sphere (shell)

## Description

In physics and applied mathematics, the mass moment of inertia, usually denoted by I, measures the extent to which an object resists rotational acceleration about an axis, and is the rotational analogue to mass. It should not be confused with the second moment of area, which is used in bending calculations.

This formula calculates the moment of inertia of a shell sphere of radius r2, with centered spherical cavity of radius r1 and mass m.

## Variables

I | moment of inertia of a shell sphere (kg*m^{2}) |

m | mass (kg) |

r_{2} | outer radius (m) |

r_{1} | inner radius (m) |