Question

How does light reflect?

Answer 1

The basic idea is that the light interacts with the electrons of the atoms. Depending on the energy (colour) of the light, the photons (light particles) are absorbed by the electrons of the atoms the material consists of, and the excited atom then emits a new photon.

The law of reflection can be explained better with the wave model of light. Imagine that a light wave hits a surface. The electromagnetic wave wiggles the charged particles (electrons and nuclei), but on the surface, they can only be wiggled in a certain direction which is determined by the direction the wave came from and the direction of the surface. Accelerated charged particles emit an electromagnetic wave, so a new wave is created. The direction of the wave is determined by the direction in which the particles wiggled.