JEE Mains · Physics · STD 12 - 12. atoms
If Rydberg's constant is \(R\), the longest wavelength of radiation in Paschen series will be \(\frac{\alpha}{7 R}\), where \(\alpha=\)____________
- A \(144\)
- B \(155\)
- C \(188\)
- D \(120\)
Answer & Solution
Correct Answer
(A) \(144\)
Step-by-step Solution
Detailed explanation
Longest wavelength corresponds to transition between \(n=3\) and \(n=4\) \( \frac{1}{\lambda}=R Z^2\left(\frac{1}{3^2}-\frac{1}{4^2}\right)=R Z^2\left(\frac{1}{9}-\frac{1}{16}\right) \) \( =\frac{7 R Z^2}{9 \times 16} \)…
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