The ratio of the frequenices of the long wavelength llmits of Lyman and balman series of hydrogen spectrum is

Options

A. `27 : 5`
B. `5 : 27`
C. `4 : 1`
D. `1 : 4`

Answer

A

Explanation

For Lyman series
`v_("Lymen") = (c )/(lambda_(max)) = Rc[(1)/((1)^(2)) - (1)/((2)^(2))] = (3RC)/(4)`
For Balmer series
`v_("Balmer") = (c )/(lambda_(max)) = Rc[(1)/((2)^(2)) - (1)/((3)^(2))] = (5RC)/(36)`
`(v_("Lymen"))/(v_("Balmer")) = (27)/(5)`