How is this the same as this? (two kinds of waves)

[physicsmaster123]

TL;DR Summary

How is this the same as this?

 

[fresh_42]

I only see $\ddot y +y =0.$ What do you mean?

 

[Ibix]

They aren't the same.

Perhaps you could add some context to the question.

 

[kuruman]

What are we comparing? There is one kind of this on the left hand side and two kinds of thises on the right hand side. This goes to show that we need more information on this.

 

[Sciencemaster]

Imagine a large surface of water. Now imagine that this water is waving in one direction. At every point on the surface of the water, the waves are moving in the same direction. If you were to look at the surface of this water from the side (perpendicularly to the direction of wave motion), you would find that the surface looks like your image on the left.

Now move your perspective so that you are looking at the same surface of water from above. It's a nice sunny day, and the sunlight reflects off of the top of the waves, while casting a shadow in the troughs. This is essentially what you are seeing on the left side of the right image. The purple spots are the crests of waves, while the dark spots are troughs.

In short, they both represent similar waves, but from different perspectives--one from the side, and one from above. Hope this helps!

 

[physicsmaster123]

Ahhh, yes that makes a lot of sense now thanks!

 

[Sciencemaster]

Ahhh, yes that makes a lot of sense now thanks!

No problem. Glad I could help!

 

[PeroK]

The "science master" helps the "physics master", I see!