Two hydrogen atoms are in excited state with electrons in`n=2` state.First one is moving to wards left and emits a photon.' of energy `E_(1)` towards right. Second one is moving towards right with same speed and emits a photon of energy `E_(2)` towards right. Taking recoil of nucleus.into account during_emission process :

Options

A. `E_(1) gt E_(2)`
B. `E_(1) lt E_(2)`
C. `E_(1) = E_(2)`
D. information insufficient

Answer

B

Explanation

In the first case, `HE of H` atom increases due to recoil whereas in the second case `KE` decrease due to recoil.
`E_(2) gt E_(1)`