The physics of a pinewood derby

I am hard at studying and then my brain starts to wander and before I know it I am on YouTube; the site that can cause any determined student to suddenly lose all concentration. And then somehow through the incredible maze of related videos I find myself at a video showing how to win a pinewood derby race with science. Little did I know that it would serve as review with plentiful information on the conservation of energy and also how both Potential and Kinetic energy affect the car. The video goes to show how potential energy, which is dependent mostly of height, is transferred into kinetic energy as it travels down the track and gains speed. It also shows how some of the potential energy is transferred into heat energy through friction. It then explains how to make the fastest car you want to start with the most potential energy and get the most of that energy transferred into kinetic energy, which is dependent mostly on velocity. To maximize potential energy the weight is placed toward the top of the car. To reduce the amount of energy lost the car rides on three wheels instead of four.