EQ+Waves2

==The p-waves travel faster in the core, which is how we know that it is a solid (a metal based on how well it transfers the wave's energy). - watch the animation again and watch the p-waves when they reach the core.==

We can calculate how thick the layers are based on how long it takes the waves to pass through the Earth.
= So we can tell what's inside the earth by listening to the seismic waves!!! They're like an x-ray or an ultrasound of the Earth's core .=