- #1
fog37
- 1,568
- 108
Hello Forum,
The conservation of linear momentum is applicable when the net external force is zero or negligible compared to the internal forces. This principles is applicable to perfectly elastic, partially elastic and totally inelastic collisions.
But only for perfectly elastic collisions the mechanical energy (KE+PE) is conserved.
That said, what happens when two cars collide in a crash in an inelastic collision and the system does not move, i.e. total final momentum is zero? There is clearly a violation of the conservation of momentum, correct? All the mechanical energy is dissipated into crushing the cars. That said, I thought that the conservation principle applied to inelastic collision without problem, regardless of the deformation and loss of mechanical energy involved...
Thanks,
fog37
The conservation of linear momentum is applicable when the net external force is zero or negligible compared to the internal forces. This principles is applicable to perfectly elastic, partially elastic and totally inelastic collisions.
But only for perfectly elastic collisions the mechanical energy (KE+PE) is conserved.
That said, what happens when two cars collide in a crash in an inelastic collision and the system does not move, i.e. total final momentum is zero? There is clearly a violation of the conservation of momentum, correct? All the mechanical energy is dissipated into crushing the cars. That said, I thought that the conservation principle applied to inelastic collision without problem, regardless of the deformation and loss of mechanical energy involved...
Thanks,
fog37