Rotational inertia is the resistance of an object to changes in its rotational motion. It depends on the mass and how the mass is distributed, with greater distances from the axis of rotation increasing rotational inertia. Angular momentum is the product of rotational inertia and rotational velocity, and is conserved for an object experiencing no external torque. A rotating frame of reference can simulate gravity through an outward centrifugal force.

1. CHAPTER 12 ROTATIONAL MOTION Rotational objects tend to keep rotating while non-rotating objects tend to remain non-rotating.