How is momentum lost in real life?

AI Thread Summary
Momentum is not lost in real life but can appear to change due to external forces like friction or heat, which primarily affect kinetic energy. When a car brakes and stops, its momentum decreases, but this change is due to the interaction with the environment, not a loss of momentum itself. In physics, momentum is conserved in a closed system, meaning that if the right reference frame is chosen, momentum remains constant. The discussion highlights that perceived momentum loss is a result of external influences rather than an actual loss. Understanding these concepts clarifies the nature of momentum in real-world scenarios.
HoneyPancake
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Just a quick question about conceptual stuff.

How is momentum lost in real life? Is it because of friction or heat? Yet that only affects kinetic energy, which means that momentum should still be conserved. So, what else is there?
 
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A momentum loss implies a change in momentum, down to a lower value. When a car is traveling at a certain speed on a road, and the driver applies the brakes and comes to a stop, does the momentum of the car change? Is momentum conserved? Why or why not? And wecome to PF!
 
If you choose the right reference frame, no momentum is ever "lost" in real life.
 

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