Momentum can be defined as “mass in motion.” All objects have mass; so if an object is moving, then it has momentum – it has its mass in motion. The amount of momentum that an object has is dependent upon two variables: how much stuff is moving and how fast the stuff is moving.

Momentum

In words, it could be said that the force times the time equals the mass times the change in velocity. In physics, the quantity Force • time is known as impulse.

Impulse

If total kinetic energy is not conserved, then the collision is referred to as an inelastic collision. Or, we could state it as as any collision in which the total kinetic energy is not conserved.

Inelastic Collision

Bouncing off each other is known as rebounding or to rebound.

Rebound

Having a constant ratio to another quantity.

Proportional

For a collision occurring between object 1 and object 2 in an isolated system, the total momentum of the two objects before the collision is equal to the total momentum of the two objects after the collision. That is, the momentum lost by object 1 is equal to the momentum gained by object 2.

Conservation of Momentum

Velocity is a vector quantity that refers to “the rate at which an object changes its position.”

Velocity

Elastic collisions are collisions in which both momentum and kinetic energy are conserved. The total system kinetic energy before the collision equals the total system kinetic energy after the collision.

Elastic Collision

An instance of one moving object or person striking violently against another.

Collision

Acceleration is a vector quantity that is defined as the rate at which an object changes its velocity. An object is accelerating if it is changing its velocity.

Acceleration

Speed is a scalar quantity that refers to “how fast an object is moving.” Speed can be thought of as the rate at which an object covers distance.

Speed

The sum of momentum of two or more objects.

Total Momentum