A spectroscopic instrument can resolve two nearly wavelength `lambda and lambda + Delta lambda if lambda//Delta lambda` is smaller than `8000` This is used to study the spectral lines of the balmer series of hydrogen Approximately how many lines will be resolved by the instrument?

Answer

C

Explanation

The range of Balmer series is 656.3 nm to 365 nm. It can resolve `lambda` and `lambda + Delta lambda = 8000`
:. Number of wavelengths in the range
`=(656.3 -365)/3000=36`
Total number of lines `=36 +2 =38`
[Extra two is for first and last wavelength]