Why Some Things Are Transparent While Others Are Opaque

Why are glass and water see-through while metal and clouds aren’t? In this clear, story-driven explainer we follow a photon’s journey to reveal why some things are transparent and others opaque, using simple demos, animations, and everyday examples.

Join us on a visual journey that explains transparency, absorption, scattering, and reflection in plain language. You’ll learn how atoms and electrons decide the fate of light, why band gaps determine which colors a material absorbs, and how thickness and wavelength change what we can see. Expect quick home experiments (milk-in-water, thin vs thick dye), simple animations, and practical takeaways you can use to understand everyday materials like glass, plastic, metal, clouds, and colored glass.

This video covers: photon transmission, atomic absorption (why materials have color), scattering (why milk and clouds look white), metallic reflection (free-electron behavior), the Beer–Lambert thickness effect, and wavelength dependence (UV vs visible vs IR). Watch the timestamps below to jump to sections. If you enjoy clear science explained visually, hit Like, Subscribe, and tell us in the comments which material we should explore next.