Question

give to example of illustrating the law of conservation of momentum

Answer 1

As I said before to give something acceleration we must apply an external force. If there is no force then object continue its motion. For momentum change we must apply impulse, in other words there must be external applied force to change momentum of the object. If there is no force applied then momentum of the system is conserved in magnitude and direction.

Pinitial=Pfinal

To understand conservation of momentum we will examine a collision of two objects. Look at the given picture, two ball having masses m1 and m2 and velocities V1 and V2 collide. If there is no external force acting on the system; momentum of the system is conserved.



 

 

 

During the collision balls exert force to each other. From the Newton’s third law these forces are equal in magnitude and opposite in direction. We can say action and reaction to these forces. Picture given below shows these forces at the instance of collision.



 

 

 

 

Ball having m2 mass exerts force on m1 and ball having m2 mass exerts force on m1. Since collision occurs from the interaction of the bodies then time of collision or interaction must be equal.

Answer 2

Answer:

If there is no force then object continue its motion. For momentum change we must apply impulse, in other words there must be external applied force to change momentum of the object. If there is no force applied then momentum of the system is conserved in magnitude and direction.