एक उत्तेजित \(He ^{+}\)आयन, अपनी न्यूनतम ऊर्जा अवस्था में संक्रमण होने तक दो क्रमागत फोटॉन, जिनके तरंगदैर्ध्य \(108.5 \,nm\) तथा \(30.4\, nm\) है। उत्सर्जित करता है। प्रारंभिक उत्तेजित अवस्था के संगत क्वॉन्टम संख्या \(n=......\) है। \((\lambda\) तंरगदैर्ध्य के लिये फोटॉन की ऊर्जा \(E =\frac{1240\, eV }{\lambda(\text { in } nm )}) \text { : }\)

Apply the relevant identity from the chapter and substitute the values established in the previous step, keeping the original constraint in view.

Use the simplified expression to isolate the unknown, then plug the result back into the question setup to confirm the working is internally consistent.

Cross-check against a boundary or limiting case. Both the dimensional balance and the qualitative behaviour at the extreme should agree with the candidate answer.

Combine the steps above to identify the correct option. The remaining choices each fail at least one of the consistency, dimensional, or boundary checks.