Periodic travelling wave

Have you ever thrown a rock into a still pond and watched the ripples spread out from where the rock hit the water? Well, a periodic travelling wave is kind of like those ripples, except it happens in something called a wave medium, like sound or light waves.

When a wave is periodic, that means it repeats itself over and over again. Just like when you swing back and forth on a swing, you keep going back and forth in the same way over and over again. That's what a periodic wave does too.

And when a wave is travelling, that means it's moving from one place to another. It's like when you run from one end of the playground to the other.

So a periodic travelling wave is like a wave that repeats itself as it moves along. Imagine you're jumping up and down on a bouncy castle. As you jump, you make a wave travel across the bouncy castle. The wave keeps going back and forth as you keep jumping up and down, but it also moves across the bouncy castle.

That's what a periodic travelling wave is like, except instead of a bouncy castle it could be something like a guitar string or a sound wave. It's really cool because it allows us to understand how things like sound and light behave and how we can use them to communicate!