Inelastic Collisions Do Not Conserve Kinetic Energy

Incorrect Thinking

Students may conserve both momentum and kinetic energy in inelastic or completely inelastic collisions.

Why Students Think This

They may overgeneralise from elastic-collision examples or from the broad idea that energy is conserved.

Correction

Momentum is conserved for an isolated collision system. Kinetic energy is conserved only in elastic collisions; in inelastic collisions, some kinetic energy is transformed into other forms.