Orbit radius ∝ n² — set two levels, then emit or absorb
Balmer visible lines:
Transitionn=3 → n=2 (emission)
E(nᵢ)−1.51 eV
E(n_f)−3.40 eV
Photon ΔE1.89 eV
Wavelength λ656.5 nm
Frequency4.57×10¹⁴ Hz
SeriesBalmer
ColourVisible · red
Bohr Model of Hydrogen ↗ LK Forge