Question

How does moment of inertia affect angular velocity?

Answer 1

Like this:

Explanation:

The expression for angular momentum is:

`L=Ixxomega`

Where `I` is the moment of inertia and `omega` is the angular velocity.

Angular momentum is conserved so if `I` is decreased you can see from the expression that `omega` must increase.

The skater in the graphic has utilised this principle. She brings in her arms to decrease her moment of inertia. As a result her angular velocity has increased i.e she spins faster.