When one object has the potential to alter the state of motion (translational or rotational) of another object, those objects are said to interact. An object that interacts with another experiences an interaction.
Page Contents |
|---|
Motivation for Concept
There are many ways that one object can change the motion of another. A person may kick a ball across the ground, giving it a translational motion, or instead may spin a ball on their finger, giving it rotational motion. The earth changes the motion of objects through the conservative action-at-a-distance of gravity (what goes up must come down) and also through the nonconservative interaction of friction (what goes out will need some help getting back). Introductory physics incorporates several ways of describing interactions to capture some of the richness of the world.