| Term | Definition |
|---|---|
| collision | An interaction between objects where the forces exerted between them are much larger than external forces, allowing analysis of initial and final states. |
| explosion | An interaction in which internal forces within a system move objects apart. |
| momentum | A vector quantity that describes the motion of an object, equal to mass times velocity, with direction matching the velocity. |
| object model | A simplification in physics where an object is treated as a single point with properties like mass and charge, ignoring size, shape, and internal structure. |
| system | A collection of objects and their interactions that are studied together as a single unit. |
| vector | A quantity that has both magnitude and direction, which can be represented as the sum of perpendicular components. |
| Term | Definition |
|---|---|
| center of mass | The point in a system where all the mass can be considered to be concentrated for the purpose of analyzing motion and forces. |
| center-of-mass velocity | The velocity of the center of mass of a system, calculated as the total momentum divided by the total mass. |
| collision | An interaction between objects where the forces exerted between them are much larger than external forces, allowing analysis of initial and final states. |
| conservation of momentum | The principle that the total momentum of a system remains constant when no net external force acts on the system. |
| explosion | An interaction in which internal forces within a system move objects apart. |
| impulse | The change in momentum of an object, equal to the force applied multiplied by the time interval over which it acts. |
| momentum | A vector quantity that describes the motion of an object, equal to mass times velocity, with direction matching the velocity. |
| net external force | The vector sum of all forces acting on a system from outside the system. |
| Newton's third law | The principle that forces always occur in equal and opposite pairs: if object A exerts a force on object B, then object B exerts an equal and opposite force on object A. |
| system | A collection of objects and their interactions that are studied together as a single unit. |
| Term | Definition |
|---|---|
| elastic collision | A collision between objects in which the total kinetic energy of the system is conserved, remaining equal before and after the collision. |
| inelastic collision | A collision between objects in which the total kinetic energy of the system decreases, with some kinetic energy transformed into other forms of energy by nonconservative forces. |
| kinetic energy | The energy possessed by an object due to its motion, equal to one-half the product of its mass and the square of its velocity. |
| nonconservative force | A force for which the work done is path-dependent, such as friction or air resistance. |
| perfectly inelastic collision | A collision in which the colliding objects stick together and move with the same velocity after the collision. |