The ratio of energies of electron in the first excited state to its second excited state in H-atom is ......

Options

A. `1:4`
B. `4:9`
C. `9:4`
D. `4:1`

Answer

C

Explanation

The energy of electron `E=(mZ^(2)e^(4))/(8epsi_(0)^(2)h^(2)n^(2))`
`:.Eprop(1)/(2)" "` ( `:.` for hydrogen Z=1)
For first excited state `n_(1)=2` and `n_(2)=3`,
`:.(E_(1))/(E_(2))=(n_(2)^(2))/(n_(1)^(2))=(9)/(4)" ":.E_(1):E_(2)=9:4`