A car driving down the hill will have the greatest kinetic energy. Kinetic energy is a concept that is of extreme importance in Physics, and it specifically comes under the domain of classical mechanics or Newtonian mechanics. Kinetic energy can be defined as the energy that is possessed by moving objects.
According to physics, energy cannot be created or destroyed, rather it can change its forms from one to another. A moving object with kinetic energy for instance, can lose that energy in the form of sound and heat energy which will dissipate to its surroundings. This ensures the principle of conservation of energy.