Which of the following statements is true about the interaction of electromagnetic radiation with matter? 1) Photoelectric absorption involves the interaction of a photon with the nucleus of an atom. 2) Rayleigh scattering involves an inelastic collision of a photon with an outer-shell electron with negligible binding energy, after which that electron is ejected from the atom. 3) The main phenomena associated with X-ray imaging are Rayleigh scattering at low photon energies and pair production at high photon energies. 4) The main phenomena associated with X-ray imaging are photoelectric absorption at low photon energies and Compton scattering at high photon energies. 5)None of these statements are true. Please explain why. Solution 1) The statement is true. The photons with atom particles are by chance, a given photon has a finite probability of passing completely through the medium it is traversing. The probability that a photon will pass completely through a medium depends on numerous factors including the photon’s energy and the medium’s composition and thickness. The more densely packed a medium’s atoms, the more likely the photon will encounter an atomic particle. 2)False The photons doest not excite the atom when it interacts with the one or more bounded electrons. The energy is same at the end of the process, that is energy of photon is equal to the interacting atom. Therefore, it is elastic scattering. 3) This statement is true. Rayliegh scattering involves in deflection of the incoming particle, but not absorption.hence it occurs for low photon energies. Whereas the pair productionrequires very high energy as the photon interacts with the electron or nucleaus and forms postiron electron pairs. The photon must have atleast 1.022 MeV energy to interact. 4) The statement is false. As the photoelectric absorption involves in absorption of photons by atoms which have considerably high energy as discussed in first point. So statements 1 and 3 are true..

1. Which of the following statements is true about the interaction of electromagnetic radiation with
matter?
1) Photoelectric absorption involves the interaction of a photon with the nucleus of an atom.
2) Rayleigh scattering involves an inelastic collision of a photon with an outer-shell electron with
negligible binding energy, after which that electron is ejected from the atom.
3) The main phenomena associated with X-ray imaging are Rayleigh scattering at low photon
energies and pair production at high photon energies.
4) The main phenomena associated with X-ray imaging are photoelectric absorption at low
photon energies and Compton scattering at high photon energies.
5)None of these statements are true.
Please explain why.
Solution
1) The statement is true.
The photons with atom particles are by chance, a given photon has a finite probability of passing
completely through the medium it is traversing. The probability that a photon will pass
completely through a medium depends on numerous factors including the photon’s energy and
the medium’s composition and thickness. The more densely packed a medium’s atoms, the more
likely the photon will encounter an atomic particle.
2)False
The photons doest not excite the atom when it interacts with the one or more bounded electrons.
The energy is same at the end of the process, that is energy of photon is equal to the interacting
atom. Therefore, it is elastic scattering.
3)
This statement is true.
Rayliegh scattering involves in deflection of the incoming particle, but not absorption.hence it
occurs for low photon energies. Whereas the pair productionrequires very high energy as the
photon interacts with the electron or nucleaus and forms postiron electron pairs. The photon must
have atleast 1.022 MeV energy to interact.
4)
The statement is false.
As the photoelectric absorption involves in absorption of photons by atoms which have
considerably high energy as discussed in first point.
So statements 1 and 3 are true.