I have searched on google but cannot find this old physics experiment. It is most probably due to my failing memory and not choosing the right search terms I am hoping someone can recall the experiment. The experiment revolved around potential kinetic energy. it was designed to show that from a given height the potential energy of a mass was identical regardless of the path of descent. The way I recall the experiment was this. Two balls each of the same size and mass were positioned on two tracks. the tracks had different inclines. The balls were released together and although they proceeded down two different tracks they both passed the finish at exactly the same time. showing that both balls had the same kinetic energy at the bottom of the slopes. Most people would say the ball going down the steeper slope would gain more speed and therefore 'win'. If anyone can recall that experiment it seems to be a variation on Galileo’s Acceleration Experiment. having the two balls pass the finish line at the same time was very effective and it has stuck in my head. I'd love to know if there is a youtube video of the experiment I described. if not at least an explanation of how to set the experiment up.