Why does earth have different layers?

Answer: Dense materials sank when molten

Layers formed randomly — Wrong. Earth's layers didn't form randomly. They formed through differentiation - a systematic process where materials separated by density when Earth was molten. Heavier elements sank to the center while lighter ones rose to the surface.

Dense materials sank when molten ✓ — Correct! When Earth formed 4.6 billion years ago, it was molten from collision energy. Through 'planetary differentiation', denser materials (iron, nickel) sank to form the core, while lighter silicate rocks floated up to form the mantle and crust. This created distinct layers: inner core, outer core, mantle, and crust. It's like oil floating on water - materials separate by density!

Volcanic eruptions created layers — Wrong. Volcanic eruptions occur because of Earth's layered structure, they didn't create it. The layers formed during Earth's early molten state through density-driven separation. Volcanoes bring material from the mantle to the surface but don't create the basic layer structure.