Momentum & Collisions

What is momentum?

The product of an object's mass and velocity (p = mv) — a measure of how hard it is to stop a moving object

What does the law of conservation of momentum state?

In a closed system with no external forces, the total momentum before a collision equals the total momentum after it

What is a perfectly inelastic collision?

A collision where the objects stick together and move with a common final velocity afterward

What is the SI unit of momentum?

kg·m/s (kilogram-metres per second)

A 5 kg object moves at 4 m/s and a 3 kg object moves at -2 m/s (same direction is positive). What is the total momentum of the system?

14 kg·m/s