Question

A photon of energy $10.2eV$ collides inelastically with a stationary hydrogen atom in the ground state. After a time interval of the order of a microsecond, another photon collides with a energy of $15eV$ . What will be observed by the detector?

• A. One photon of energy $10.2eV$ and an electron energy $1.4eV$
• B. Two photons of energy $1.4eV$
• C. Two Photons of energy $10.2eV$
• D. One photon of energy $10.2eV$ and another photon of $1.4eV$

Answer 1

Answer: (A)

In the time of $1\mu s$ first photon is emitted, due to second photon incident ionization of atom takes from ground state ( Like photo electric effect)