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Inelastic collision
Beginner
Momentum is conserved but kinetic energy is lost.
collisionMomentum is conserved but kinetic energy decreases, converted into heat, sound or deformation. Most real collisions are inelastic.
A car crash crumples the bodies.
"Inelastic" doesn't mean momentum is lost.
In more detail
In an inelastic collision, momentum is conserved but some kinetic energy is lost, typically to heat and deformation. Most everyday collisions are inelastic.
Real-world uses
- Car crashes dissipate energy in deformation of the vehicles.
- Dropping an egg on a hard floor is an inelastic collision.
- A car crash or a dropped egg loses kinetic energy to deformation and sound, which makes the collision inelastic.
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Frequently asked questions
Is momentum conserved in an inelastic collision?
Yes. Only kinetic energy is lost.
Where does the lost energy go?
Mostly into heat, sound and permanent deformation.
Can kinetic energy increase in a collision?
Not in a normal collision. Only chemical or nuclear energy stored in the system can be released to increase the kinetic energy.
Related topics in Momentum & Collisions
Isolated system · Recoil of a gun · Elastic collision · Perfectly inelastic collision · Coefficient of restitution · Elastic head-on collision velocities