What type of collision conserves the total kinetic energy?

In an elastic collision, the total kinetic energy of the system before and after the collision remains constant. This means that while the objects may collide and change direction or speed, the overall amount of kinetic energy does not change. In such collisions, both momentum and kinetic energy are conserved.

Elastic collisions typically occur at the molecular level, such as gas particles colliding, and they are characterized by the absence of any deformation or generation of heat during the interaction. The ability of the objects to rebound without losing energy to other forms reinforces the definition of this type of collision.

Other types of collisions, such as inelastic collisions, do not conserve kinetic energy; instead, some kinetic energy is transformed into other forms of energy, such as heat or deformation. In the case of perfectly inelastic collisions, the objects stick together after colliding, resulting in a maximum loss of kinetic energy among the options provided. Fragmentation collisions typically involve breaking apart of objects, also resulting in energy loss. Therefore, the defining characteristic of elastic collisions is the conservation of kinetic energy.