Why+block+experiment+didn't+work

=**I think friction greatly affects the results of this experiment. When we did our experiment, as the length of the inclined plane decreased, the amount of work decreased. Thus, we should have the maximum length of the inclined plane in order to get the maximum amount of work. However, even with the length of the inclined plane being at 72 cm, we still got about 300J. Thus, it is impossible to increase the work with the same surface. I suggest lubricating the surface or changing to an inclined plane with a smoother surface.**=