Is the earth a solid

Answer 1

This is a very difficult question to answer with a simple response, so its going to require some explanation.

The Earth is split into multiple layers, some solid and some liquid. I'll work inward so you can see the progression.

The first layer is the Earth's crust, which is a solid. This is because of its distance from the core, and as of such does not get anywhere near enough heat to turn it into a liquid.

The second layer is the mantle, which is semi-liquid. This layer is close enough to the core to turn it into a partial liquid (imagine a thick paste).

The third layer is the outer core and this is a liquid. Because of its proximity to the core, this layer is completely liquid rock.

The final layer is the inner core and this layer is a solid. Although it is the hottest layer, the inner core remains solid because of the pressure from the other 3 layers.