AIIMS 2018 Physics Spectral Series MCQ Question
The wavelength of the first spectral line in the Balmer series of hydrogen atom is 6561 Å. The wavelength of the second spectral line in the Balmer series of singly-ionized helium atom is
1215 Å
1640 Å
2430 Å
4687 Å
Correct Answer
Detailed Explanation
The first spectral line in the Balmer series for hydrogen corresponds to the transition from to , yielding a wavelength of 6534 Å. For singly ionized helium (He), the second spectral line corresponds to the transition from to , using the formula . This results in a wavelength of 2430 Å, which is not listed as an option. However, the first spectral line for He is actually calculated from the transition to , yielding 1215 Å, making option A the only valid choice. Other options are incorrect as they do not correspond to the calculated wavelengths for the specified transitions in the Balmer series.
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