The study looked at how rain affects soil erosion by breaking down soil into smaller pieces and washing it away. They used different sizes of raindrops and depths of runoff to see how much soil was lost. They found that larger raindrops and deeper runoff caused more soil loss. The smallest soil particles were washed away the most. The size of the raindrops determined which size of soil particles were carried away by the runoff. Overall, the study showed that rain can significantly impact soil erosion by changing the distribution of soil particles.