The Law of Conservation of Momentum states that..?

Question

CHOICES:
a. The energy of the movig objects before and after impact is the same time
b. The total momentum in an isolated system is constant
c. The mass of the objects before and after collision remains the same
d. the velocity of the objects before and after collision is the same.

If you have an answer please state the reason.
Thanks!

Answer 1

b is correct. Refer to the differential form Newton's second law of motion. It states
dp/dt=F where F is the external force, p is momentum and t is time. If F=0 then dp/dt=0 which means p=constant

Answer 2

Conservation Of Momentum States

Answer 3

a. the total ammount of energy, in two objects, before collision and after collision, are the same because energy is merely transfered from one object to another. (usually faster moving yo slower moving)

even with inelastic collisions, the energy of the two objects remain the same, as energy is simply transfered into heat.

a great example of non-elastic collicions is biljards. if a ball is shot straight onto a stationary ball, youll see that at the moment of collision, the moving ball instantly stops, transfers all its energy to the ball it hits, and that ball starts moving at the same speed. you can clearly see it in this movie.

http://www.youtube.com/watch?v=Bqxdnhl-DNU

c is a true statement aswell, but that is not the law of conservation of motion

Answer 4

The dificulty of the question is that there are two scenarios when two masses interact in collison ;ONe is Perfectly Elastic collison where momentum is conserved and and the Other is Inelastic collison where momentum is not conserved.
In reality according to relativity theory the law of conservation of momentum is really moot.The reason is that as per Relativity Theory momentum is not conserved.