What is an isolated system?
An isolated system is a system that doesn't exchange any matter or energy with its surroundings. This means there are no external forces acting on the system.
What is momentum?
Momentum is a measure of an object's mass in motion. It's calculated by multiplying an object's mass (m) by its velocity (v):
* Momentum (p) = mass (m) x velocity (v)
Conservation of Momentum:
The law of conservation of momentum states that the total momentum of an isolated system remains constant. This means:
* The total momentum before an interaction is equal to the total momentum after the interaction.
Why change of momentum is zero:
In an isolated system, since there are no external forces, the total momentum of the system remains constant. If the momentum doesn't change, then the change in momentum is zero.
Example:
Consider two objects of equal mass colliding in an isolated system (like space, far away from any gravitational influence). Before the collision, each object has a certain momentum. During the collision, the objects exchange momentum, but the total momentum of the system remains the same.
Key takeaway:
The change in momentum within an isolated system is zero because the total momentum is conserved. This is a consequence of the fundamental law of conservation of momentum, which holds true due to the absence of external forces.
