How do you know sound is a wave form?

Answer 1

The frequency we hear at is demonstrated in a wave-like pattern. Sound itself is not like little waves coming at us. Just for us to have a visual representation of what it is, the waves on the screen are the best format. Its similar to dropping a rock in a pool. The waves go out from the rock and slowly dissipate and eventually dissapear, just like the further you walk away from someone the less you hear them, and eventually not at all.