Question

A hydrogen atom in the ground state is excited by monochromatic radiation of wavelength `lambda A`. The resulting spectrum consits of maximum 15 different lines. What is the wavelength `lambda`?`
A. `937.3 Å`
B. `1025 Å`
C. `1236 Å`
D. None of these

Answer 1

Correct Answer - 1
Total number of spectral lines given by
`(1)/(2)[n-1]xxn=15," ":.n=6`
Thus, electron is excited upto `6^(th)` energy level from ground state. Therefore,
`(1)/(lambda)=R_(H)[(1)/(1^(2))-(1)/(n^(2))]=109737xx(35)/(36),`
`lambda=9.373xx10^(-5)cm=937.3Å`