If the series limit frequency of the Lyman series is `v_(L)`, then the series limit frequency of the Pfund series is ......

Options

A. `25v_(L)`
B. `16v_(L)`
C. `(v_(L))/(16)`
D. `(v_(L))/(25)`

Answer

D

Explanation

`hf_(L)=E_(0)[(1)/(n_(1)^2)-(1)/(n_(2)^(2))]`
`=E_(0)[(1)/(1^(2))-(1)/(oo^(2))]" "n_(1)=1,n_(2)=oo`
`:.hf_(L)=E_(0)" "....(1)`
`hf_(P)=E_(0)[(1)/(n_(1)^(2))-(1)/(n_(2)^(2))]`
`=E_(0)[(1)/(5^(2))-(1)/(oo)]" "n_(1)=5,n_(2)=oo`
`:.hf_(P)=(E_(0))/(25)" "......(2)`
Taking ratio of equation (1) and (2),
`:.(f_(L))/(f_(P))=25`
`:.f_(P)=(f_(L))/(25)`