Let `E=(-1me^(4))/(8epsilon_(0)^(2)n^(2)h^(2))` be the energy of the `n^(th)` level of H-atom state and radiation of frequency `(E_(2)-E_(1))//h` falls on it ,

Options

A. it will not be absorbed at all
B. some of atoms will move to the first excited state
C. all atoms will be excited to the `n=2` state
D. all atoms will make a transition to the `n=3` state

Answer

B

Explanation

The given energy of `n^(th)` level of hydrogen atom is `E_n=-(me^4)/(8epsilon_0^2n^2h^2)` Since all the H-atom are in ground state `(n=1)` then the radiation of given freqency `(E_2-E_1)/(h)` falling on it may be absorbed by some of the atoms and move them to the first excited state `(n=2)`.