Question

Materials in Earth's interior?

Answer 1

Answer:

The inner core is the Earth's "interior".

P-waves pass through both the mantle and core, but are slowed and refracted at the mantle / core boundary. Whereas, S-waves pass from the mantle to the core and are absorbed due to shear waves being incapable of transmitting through liquids. Therefore, this is (further) proof the outer core does not behave like a solid substance.