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92 experiments / 15 branches

QUANTIZATION

Energy arrives in whole packets and sits on whole rungs — nature counts before it measures.

BLACKBODY

P = εσAT⁴ and λ_max = b/T — Stefan, Wien, and the Planck curve that broke classical physics.

5 STAGES · 6 TERMS

PHOTOELECTRIC

E = hf − φ — below threshold, a floodlight ejects nothing; above it, a glimmer.

5 STAGES · 8 TERMS

BOHR ATOM

Only the rungs exist — and the jumps between them are Balmer’s lines, to the nanometer.

5 STAGES · 8 TERMS

MATTER WAVES

λ = h/p: an electron at 100 eV waves at 1.22637 Å — atom-sized, and the microscope is born.

5 STAGES · 6 TERMS

THEORY IN PLAY — Interactive Physics ·

Pause at stages ←→ step · PgUp/Dn stage · Space play

Speed Loop scene

Given

Computed