What principle best explains how angular momentum is conserved in a falling cat?

The conservation of angular momentum is a crucial principle when analyzing the behavior of a falling cat. When a cat falls, it has rotational motion in addition to its translational motion. As the cat begins to fall, it can change its orientation by rotating its body and legs to land on its feet. This ability to twist its body during fall is a demonstration of how angular momentum is conserved.

Angular momentum is defined as the product of an object's moment of inertia and its angular velocity. In a closed system like the cat, the total angular momentum must remain constant if no external torques are acting on it. When the cat tucks in its legs or spreads them out, it alters its distribution of mass, which affects its moment of inertia. To conserve angular momentum, the cat will adjust its angular velocity, thereby allowing it to rotate in such a way that it lands on its feet.

This fascinating ability showcases the principle of conservation of angular momentum, where the cat’s actions are governed by physical laws that dictate that without external influence, its total angular momentum remains constant throughout the fall.