It started at the age of five , when we used to play with this toy,we pulled it,we pushed it ,we threw it,we crushed it and sometimes we even slept with it .And now fourteen years hence, we are looking at the same object but in an entirely different perspective.The pull back car is one of the most common childhood toys , with which almost all of us must have played.The car , when pulled backward by some distance on a surface and left goes forward a distance greater than the backward one , but the reverse does not happen.This mechanism is also employed in the toys driven by keys but with a slight difference.The basic cause and effect are the same.