Conversation so far:
what is the significance of mass moment of inertia
Rotational inertia is used to calculate angular momentum and allows us to explain (via conservation of angular momentum) how rotational motion changes when the distribution of mass changes.
what is the symbol for mass moment of inertia
The common symbol for Moment of inertia is I.
what is the si unit for mass moment of inertia
The SI unit for Moment of inertia is kg m^2

Question: how is the moment used by people
Self-contained rewrite: how is the moment used by people