What is the affect on this? A wave is transmitted into a medium where it moves faster, and then back into a medium where it moves slower again.

As a wave travels through a medium, it will often reach the end of the medium and encounter an obstacle or perhaps another medium through which it could travel. The behavior of a wave (or pulse) upon reaching the end of a medium is referred to as boundary behavior. When one medium ends, another medium begins; the interface of the two media is referred to as the boundary and the behavior of a wave at that boundary is described as its boundary behavior. The questions that are listed above are the types of questions we seek to answer when we investigate the boundary behavior of waves.

i don,t know so just answer mine