The wavelength of the first spectral line of the Lyman series is `lambda` then the wavelength of the first spectral line of the Paschen series is .........`lambda`

Options

A. `108//7`
B. `28//5`
C. `7//108`
D. `5//27`

Answer

A

Explanation

`1/(lambda) = R(1/1^2 - 1/2^2)`
`implies 1/(lambda_1) = R(1/(3^2) - 1/(4^2))`
`implies (lambda_1)/(lambda) = (3/4)/(7/(16xx9))`
`implies lambda_1 = 3/4 xx (16xx9)/(7) lambda`
`implies lambda_1 = (108)/(7) lambda`