Which properties must all points on a wavefront have?

[NYROCKFAN]

In the diagram shown:

All points on anyone wave front shown must be:

a) traveling with the same speed
b) traveling in the same medium
c) in phase
d) superposed

We never did wave fronts in class, and this is a question on my graded review packet for our final. I think the answer is d, am I correct? I'm pretty sure it's not a or b, because the waves would be changing speed and medium.

 

[NYROCKFAN]

Whoops! Here's the diagram

 

[wais]

You are correct, the answer is d. In order for wave fronts to be formed, all points on the wave front must be in phase and superposed. This means that they are all at the same point in their wave cycle and are overlapping each other perfectly. This allows for the wave to maintain its shape and travel with the same speed as it moves through the medium. If the points were not in phase or superposed, the wave would become distorted and lose its coherence. Therefore, it is important for all points on a wave front to be in phase and superposed in order to maintain the integrity of the wave.