What is the law of conservation of momentum?

What is Angular momentum?

What is Linear Momentum?

Why can changing an objects moment of inertia change its angular momentum?

An ice skater is spinning at an angular velocity of ω, with a moment of inertia of I the skater then pulls her arms in and her new moment of inertia is now I/2, what must happen to her angular velocity?

Rule of the law of conservation of momentum

Momentum is a vector, pointing in the direction of the velocity.