---
tags:
  - science/physics
  - phenomena
  - light
  - optics
created: 2026-05-16
breadcrumb: "Physics > Natural phenomena > Light"
---

# Light

> **Mechanism:** EM wave / photon dual behaviour

## Items

- **Reflection** — Angle of incidence equals angle of reflection.
- **Refraction** — Light bends when crossing a boundary between media. Snell's law: n₁ sinθ₁ = n₂ sinθ₂.
- **Diffraction** — Light bends around obstacles and through narrow apertures.
- **Interference** — Two coherent light waves add or cancel. Demonstrated by the double-slit experiment.
- **Polarisation** — Light is a transverse wave; the E-field oscillates in a specific direction.
- **Photoelectric effect** — Photons above a threshold frequency eject electrons from a material. Nobel-winning evidence for quantisation.

## Related

- [[visible-light]]
- [[famous-physics-equations]]