Newton's Third Law:

* "For every action, there is an equal and opposite reaction." This law describes the *interaction* between two objects. When one object exerts a force on another (action), the second object exerts an equal and opposite force back on the first object (reaction).

Conservation of Momentum:

* The total momentum of a closed system remains constant. Momentum is a measure of mass in motion (mass x velocity). In a closed system (one where no external forces act), the momentum of all the objects within the system before an interaction is equal to the momentum of all the objects after the interaction.

The Connection:

Newton's Third Law is the foundation for the Law of Conservation of Momentum. Here's how:

1. Equal and Opposite Forces: When two objects interact, the forces they exert on each other are equal and opposite.

2. Change in Momentum: These forces cause a change in momentum for each object. The force acting on object A causes a change in momentum of object A, and the force acting on object B causes an equal and opposite change in momentum of object B.

3. Total Momentum Remains Constant: Because the changes in momentum are equal and opposite, the *total* momentum of the system remains constant.

In Summary:

Newton's Third Law describes the interaction between objects (forces), while the Law of Conservation of Momentum describes the overall result of that interaction (constant total momentum).