Previous Knowledge:

I had a ramp that had a 20 degree incline. I rolled objects off it at 5 different distances, from .2, .4, .6, .8, and 1 meter. It was .50kg and it came in 4 shapes, a box, a ball, a hoop, and a disk. I calculated the percent change in Average U_g and Average K for all shapes. The box was 1.1%, the ball was 30.7%, the hoop was 65.8%, and the disk was 50.3%.

Question:

Why does the shape of the object affect the percentage of energy change as it moves down a ramp? Why did the box have a much lower percent than the other shapes even though they were all .50kg?

(Air resistance is ignored, uncertainty is ignored, but there is possibility of friction.)