An excited hydrogen atom returns to the ground state . The wavelength of emittted photon is ` lambda` The principal quantium number fo the excited state will be :

Options

A. ` [(R+1)/(lambdaR)]^(2//2)`
B. `[lambdaR (lambdaR + 1) ]^(1//2)`
C. ` [(R+1)/(lambdaR-1)]^(2//2)`
D. `[1/(lambdaR (lambdaR+1))]^(1//2)`

Answer

C

Explanation

`1/(lambda) = R [1/n_1^2 - 1/n_2^2]`
` R[1/1^2 - 1/n^2]`
` :. N=[(lambdaR)/( lambdaR-1)]^(1//2)`