The law of universal gravitation describes the force of attraction between any two objects with mass. It does not state anything about the total momentum of interacting objects.

Here's why:

* Newton's Law of Universal Gravitation: This law states that every particle in the Universe attracts every other particle with a force that is proportional to the product of their masses and inversely proportional to the square of the distance between their centers.

* Momentum: Momentum is a measure of mass in motion, calculated as mass multiplied by velocity. It is a vector quantity, meaning it has both magnitude and direction.

* Conservation of Momentum: The principle of conservation of momentum states that the total momentum of a closed system remains constant over time. This means that in a closed system, momentum is not lost or gained, only transferred between objects.

The Law of Universal Gravitation and Conservation of Momentum:

While the law of universal gravitation describes the force that causes interactions between objects, it doesn't directly deal with momentum. The force of gravity can lead to changes in momentum, but the total momentum of the interacting system will still be conserved.

Example:

Imagine two objects in space, A and B, attracting each other due to gravity. As they move closer, their velocities change, and therefore their momenta change. However, the total momentum of the system (A + B) remains constant. Any momentum lost by one object is gained by the other.

In conclusion, the law of universal gravitation describes the force of attraction between objects with mass, while the principle of conservation of momentum describes how momentum is transferred within a closed system. These are two distinct concepts.