Bohr orbits of hydrogen (to scale): rₙ = n²a₀हाइड्रोजन की बोर कक्षाएँ (पैमाने पर): rₙ = n²a₀Bohr orbits of hydrogen (to scale): rₙ = n²a₀

NCERT §12.4 · Class 12 Physics · Chapter 12 · interactive diagram

Parts and what they mean

• Nucleus (proton) (नाभिक (प्रोटॉन)) — Charge +e at the centre.
• n = 1 orbit (Bohr radius a₀) (n = 1 कक्षा (बोर त्रिज्या a₀)) — r₁ = a₀ = 0.529 Å = 5.29 × 10⁻¹¹ m. Energy −13.6 eV (ground state).
• n = 2 orbit (n = 2 कक्षा) — r₂ = 4a₀ = 2.12 Å. Energy −3.40 eV.
• n = 3 orbit (n = 3 कक्षा) — r₃ = 9a₀ = 4.76 Å. Energy −1.51 eV.
• n = 4 orbit (n = 4 कक्षा) — r₄ = 16a₀ = 8.46 Å. Energy −0.85 eV.
• Transition n = 3 → n = 2 (संक्रमण n = 3 → n = 2) — The electron does not travel through the space between orbits in Bohr’s model; it simply goes from one stationary state to another.
• Emitted photon (उत्सर्जित फ़ोटॉन) — hν = E₃ − E₂ = −1.51 − (−3.40) = 1.89 eV → λ = 656 nm (red Hα line).

Original diagram drawn by Simple Learning Hub, based on NCERT §12.4. Report a mistake