If `R` is the Rydberg's constant for hydrogen the wave number of the first line in the Lyman series will be

Options

A. `(R )/(4)`
B. `(3R)/(4)`
C. `(R )/(2)`
D. `2R`

Answer

B

Explanation

For Lyman series
`bar(v) = (1)/(lambda) = R ((1)/(1^(2)) - (1)/(n^(2)))` here `n = 2, 3, 4, 5` …….
For first line
`bar(v) = R ((1)/(1^(2)) - (1)/(2^(2))) rArr bar(v) = R (1-(1)/(4)) = (3R)/(4)`