What happens when a wave hits a surface?

During with project I was partnered with Adrian, we experimented to see what would happen when a wave hits the surface. To find the answer to this question we used a piece of paper which we laid right next to the wall. This paper we used to track our findings, we first tried using marker but it turned out that we weren't being very accurate while trying to follow the ball. So instead of using marker we simply wet the ball and using the marks it made on the paper, drew it's path. To conduct this experiment we rolled a ball against the wall and let it bounce back. What we found out it that is you roll the ball at a certain angle it would rebound in the opposite direction. Almost like a reflection and if you look at the diagram below it pretty much explained what happened except it was a wave to really a ray and instead of a mirror there was a wall:
All the wave paths generally looked like this except for if we rolled it at a straighter angle, if this happened the angle would not be as big and it would be more like a straight back and forth line. Another variable that made the answer different was the power with which we threw it. The harder we rolled it the harder it would ricochet back making it a full line to the wall and back. Yet of we threw it with less force it would make the ball go slower and it would sometimes stop halfway through the paper. So, to conclude when a wave hits a surface it will ricochet back, and the force and length of it coming back depend on power and angle. The proper names for these angles is the Angle of Incidence, the angle which actually goes towards the "barrier", and the reflection is called the Reflected ray. These rays follow the law of reflection which is for every angle of incidence there is a angle of reflection.