A photon collides with a stationary hydrogen atom in ground state inelastically. Energy of the colliding photon is 10.2 eV. After a time interval of the order of micro second another photon collides with same hydrogen atom inelastically with an energy of 15eV. What wil be observed by the detector?
(a) 2 photons of energy 10.2 eV
(b) 2 photons of energy 1.4 eV
(c ) One photon of energy 10.2 eV and an electron of energy 1.4 eV
(d) One photon of energy 10.2 eV and another photon of energy 1.4 eV

Options

A. `2` photon of energy `10.2 eV`
B. `2` photon of energy `1.4 eV`
C. One photon of energy `10.2 eV` and an electron of energy `1.4 eV`
D. One photon of energy `10.2 eV` and another photon of `1.4 eV`

Answer

C

Explanation

Due to `10.2 eV` photon one photon of energy `10.2 eV` will be detected.
Due to `15 eV` photon the electron will come out of the atom with energy `( 15 - 13.6) = 1.4 eV`.