Unraveling the Mystery of Wave Collisions: Same Amplitude Interaction

[Nusc]

Say we have two waves of the same amplitude are about to collide with each other.

The preceeding wave travels at a slightly higher speed before interacting with the final wave. However, instead of passing through the final wave its speed and size is transferred into the final wave where it now possesses the properties of the final initial wave. This is truly bizare. This feature only occurs for waves with the same amplitude, whereas an interaction like in figure 2, a large wave merges with a small wave for a finite amount of time with the large wave decreasing in amplitude and the small wave increasing in amplitude, then restoring its initial form after collision.

Can anyone explain to me why waves of the same amplitude behave this way?

 

[lpfr]

You are working with waves in a non-linear medium. That is, the speed of waves depends on its amplitude. When a wave catches another the speed of the sum is different of the speed for each one. What happens then depends on the dependence of speed with the amplitude and the shape of the waves. It depends on the media. The behavior you describe is just one possibility.