How Small Are We In The Universe?

Sumo Wrestling - Bigger Is Better?

small mass, low speed (= smaller kinetic energy) VS large mass
simply put, the boy does not have enough kinetic energy to move the larger-sized sumo wrestler

Competition - for breeding grounds

Energy Cannot Be Created or Destroyed...

....but it can be converted from one form to another

Evidently (from the demonstration) there is a loss of energy when the ball swings back.
So 'where' did the energy go to?