Master the Mechanics: NCEA Level 3 Physics 2026 – Get Ready to Rock Your Exam!

In an inelastic collision, kinetic energy is not conserved while momentum is conserved. This means that during the collision, some of the kinetic energy is transformed into other forms of energy, such as heat, sound, or potential energy due to deformation of the objects involved. An example of an inelastic collision is a car crash, where the vehicles crumple and generate sound and heat, demonstrating a loss of kinetic energy that does not get transformed into another mechanical form.

In contrast, elastic collisions are characterized by the conservation of both momentum and kinetic energy. Perfectly elastic collisions are a specific subset of elastic collisions where, in addition to conserving kinetic energy, the objects also do not undergo any deformation or generation of heat. Explosive collisions, while they may have different energy dynamics, typically result in the production of energy and may not reflect the conservation characteristics described in the context of collisions. Therefore, the defining feature of inelastic collisions is the lack of kinetic energy conservation, making this the correct classification.