Which collision causes deformation, heat, and may result in sticking, but is not perfectly inelastic?

• A. Elastic Collision
• B. Perfectly Inelastic Collision
• C. Momentum
• D. Inelastic Collision

Answer: (D)

Collisions are categorized by how much kinetic energy is lost and whether the bodies deform. Inelastic collisions are those where kinetic energy is not conserved and the colliding objects typically deform, converting some kinetic energy into internal energy, heat, and sometimes sound. Sometimes deformation leads to sticking, but not always; when objects stick together after the collision, that’s a perfectly inelastic collision. The description here includes deformation and heat and the possibility of sticking, but not necessarily sticking, which matches an inelastic collision. Elastic collisions would show no permanent deformation or heat and would conserve kinetic energy. So this scenario best describes an inelastic collision.