Question

which best explains how the collisions of materials in space contribute to the formation of layers in protoplanets?
the materials undergo decay when they collide, which results in the heating and subsequent melting and rising of materials.
the collisions release heat, which results in the heating and subsequent melting, sinking, and rising of materials.
the materials undergo decay when they collide, which results in the cooling and subsequent hardening and sinking of materials.
the collisions absorb heat, which results in the cooling and subsequent hardening and rising of materials.

Explanation:

When materials in space collide, kinetic energy is converted into heat (through inelastic collisions). This heat causes materials to melt. Denser materials sink (due to gravity) and less - dense materials rise, creating layers. Option 1 is wrong because decay is not the main cause of heating in this context. Option 3 is incorrect as decay - induced cooling is not relevant here. Option 4 is wrong because collisions release heat, not absorb it.

Answer:

The collisions release heat, which results in the heating and subsequent melting, sinking, and rising of materials.