What are some common examples of momentum conservation

What are some common examples of momentum conservation in your daily life? Explain how you can apply the law of conservation of momentum to one of these examples.

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Christopher A:

As I work in as a traffic investigator, momentum is always a factor in traffic accidents. For these collisions in serious accidents, we look for the total momentum before the collision and the total momentum after the collision. With the help of technology and how vehicles use computers systems now days, it has become much easier to find the momentum at the time of impact. This information is stored on the computers in vehicles.

Another example in my line of work I carry a firearm as well. When the bullet is fired from the gum, there is a certain amount of force that forces the bullet out of the barrel, When the bullet is forced out of the barrel, it causes the gun to recoil.