To increase angular velocity, what must a performer do with their moment of inertia?

• A. Increase moment of inertia.
• B. Decrease moment of inertia.
• C. Extend limbs.
• D. Increase body mass.

Answer: (B)

To increase angular velocity, you must reduce the moment of inertia. Angular momentum L equals I times ω, and when no external torque acts, L stays the same. If you lower I, the spin must speed up to keep L constant. That’s why tucking in the arms or drawing limbs closer to the body makes you spin faster. Extending limbs or adding mass increases the moment of inertia and would slow the rotation.