As a life gaurd I have the responsibility to work in the morning at times. This means coming in to school at 5:45 am and guarding for people who decide to do laps. Recently a gentleman came in and was somewhat rude and impatient. This is something I really don't care about to much but he was a rather large fellow amd was the first one to enter the still pool via a canon ball near the gaurd chair. After I got over the immediate displeasure at being soaked I noticed how in the pool his mass had created waves that traveled across the pool in a quick pulse which upon reaching the other side of the pool and reflected back. Due to his movement in the water following the wave became impossible. I noticed this several more times after the wave unit began in physics. When the first person gets in you can watch the wave travel reflect and lose energy over time.