Question

What is conservation of angular momentum?

Answer 1

see below

Explanation:

For linear motion we have the conservation of linear momentum(mass `xx`linear velocity): that is in any system, providing no external forces act, the total linear momentum is always constant.

For rotational bodies we have another conservation law. Providing NO external Torques act, the total angular momentum
(moment of inertia `xx` angular velocity) is constant.