<human>:  When a car is going down a hill, what is the angular momentum of the car?
<bot>: The angular momentum of the car is the same as the angular momentum of the car’s wheels. Angular momentum is a measure of the rotational motion of an object. Angular momentum is a vector quantity, which means that it has both a magnitude and a direction. The magnitude of the angular momentum is the product of the object’s mass and its velocity. The direction of the angular momentum is the direction of the object’s velocity.