Intertia is the tendency of an object to maintain its velocity: if an object is at rest, it has the tendency to remain at rest; if it is moving, the tendency is to keep moving with the same velocity. That is what happens if no forces act on the object; if forces act on the object, including gravitation, friction, and others, its velocity will change.
That depends, in what direction it is moving initially, and at what speed. Inertia is the tendency to MAINTAIN a velocity.
Momentum depends on mass and velocity.
Inertia
The velocity of a moving object....
INERTIA. This is not an 'ability', but rather a PROPERTY of Matter.- Newtons First Law, "inertia", the propety of matter defined by a still object's tendency to stay at rest, and a moving object's tendency to keep moving at the same velocity.
Momentum
Momentum
That would be Newton's 1st Law of Motion.
I assume you mean, when the car starts moving. The car starts moving; the coffee cup "wants to", or has the tendency to, keep its previous velocity, so it has the tendency of NOT following the movement of the car.
I suppose you mean "inertia". That is the tendency of an object to remain at rest if it is resting, or to keep moving (at a constant velocity) if it is moving.
Both momentum and kinetic energy depend on mass and velocity.