How can light be both a ray, a wave and a particle?
Light behaves like a ray when it hits a surface, like a wave when it passes through two slits, and like a stream of particles when you try to catch it. The skill is knowing which description fits which experiment.
Snell’s law is the ray picture and works for lenses, fibres and water. The double slit breaks the ray picture and needs waves. What happens when you add a detector is the start of quantum mechanics.
- 1 Simulation
Snell’s law: how light bends, reflects and gets trapped
Start with rays: how light bends, reflects or gets trapped at a surface.
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What is Young’s Double-Slit Experiment ? And its importance for beginners
Where the ray picture fails: Young’s original experiment and why it mattered.
- 3 Simulation
Double slit experiment: waves, particles and watching the slits
Run it yourself, then add a detector at the slits and watch the pattern disappear.
- 4 Article
Variations of the Double-Slit Experiment: Brief Overview
The variants, from single electrons to delayed choice.
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