Waves & Optics
Sound, light, interference and lenses.
Waves
How Double-Slit Interference Works and Why It Matters
How two narrow slits make light and matter waves interfere, how to calculate fringe positions, and why the experiment shaped quantum theory.
WavesHow Refraction Works: Snell's Law and Why Light Bends
How light bends at a boundary between materials, how Snell's law predicts the new angle, and why refractive index controls how much the light bends.