Here's why:
* Angular velocity (ω) is a vector quantity that describes the rate of change of angular position. Its direction is given by the right-hand rule: if you curl your fingers in the direction of rotation, your thumb points in the direction of ω.
* Angular momentum (L) is also a vector quantity and is defined as the product of the moment of inertia (I) and the angular velocity (ω): L = Iω. Since I is a scalar quantity, the direction of L is the same as the direction of ω.
What changes when angular velocity decreases is the magnitude of both angular velocity and angular momentum.
* Decreasing angular velocity: The magnitude of ω is getting smaller, meaning the object is rotating slower.
* Decreasing angular momentum: Since L is directly proportional to ω, the magnitude of L will also decrease as ω decreases.
In summary: Even when angular velocity is decreasing, the direction of both angular velocity and angular momentum remain the same. Only their magnitudes are changing.
