Atoms

Alpha scattering — toggle Thomson (pudding) vs Rutherford (point nucleus). Coulomb deflection.

Circular orbits rₙ = n²a₀/Z with standing wave pattern nλ = 2πr.

Eₙ = −13.6 Z²/n² eV — horizontal levels with continuum above the ionization limit.

Rydberg: 1/λ = R(1/n₁² − 1/n₂²) — selector for Lyman, Balmer, Paschen, Brackett, Pfund.

All 5 series on a log-wavelength axis with visible-band zoom toggle.

Click a level pair — photon animates out with wavelength-matched color.