Momentum
Momentum is the product of a moving object's massThe amount of matter an object contains. Mass is measured in kilograms (kg) or grams (g). and velocityThe speed of an object in a particular direction..
\(\text{Momentum} = \text{mass}\times \text{velocity}\)
The symbol for momentum is \(p\) so this can also be written as:
\(p=mv\)
Momentum is measured in kg ms-1.
Momentum is a vectorA vector describes a movement from one point to another. A vector quantity has magnitude (size) and direction. quantity that depends on the direction of the object. Momentum is of interest during collisions between objects.
When two objects collide the total momentum before the collision is equal to the total momentum after the collision (in the absence of external forces).
This is the law of conservation of momentum. It is true for all collisions.
Watch this video for a practical demonstration of conservation of momentum in elastic collisions.
Watch this video for a practical demonstration of conservation of momentum during inelastic collisions.