Uploaded October 2025 | Updated September 2026, 3 weeks ago

---

This is a simple at-home experiment you can do to prove light is a particle, and measure Planck's constant (the fundamental constant that sets the scale of quantum mechanics).

KiwiCo delivers hands-on projects that make learning fun. Get 50% off your first crate with code LOOKINGGLASS at kiwico.com/lookingglass

Animations by the extremely talented Kathy Sarpi! kathysarpi.com