ASNT Radiographic Testing Practice Test 2025 – Comprehensive All-in-One Guide for Exam Success!

Gamma and x-radiation can interact with matter primarily through processes such as photoelectric absorption, Compton scattering, and pair production.

Photoelectric absorption occurs when a photon is completely absorbed by an atom, resulting in the ejection of an electron from one of its inner shells. This process is significant at lower energies of x-rays and gamma rays and is strongly dependent on the atomic number of the absorbing material.

Compton scattering involves the interaction of a photon with a loosely bound outer shell electron. The photon loses energy and is scattered at a different angle, while the electron is ejected from the atom. This interaction is dominant in a range of energies and contributes significantly to the attenuation of x-rays and gamma rays in materials.

Pair production occurs at higher photon energies (above 1.022 MeV when the photon energy exceeds the combined rest mass energy of an electron and positron). In this process, a photon can create a pair of particles: an electron and its antiparticle, a positron, when it comes into the vicinity of a nucleus.

In contrast, the other answer choices involve different physical phenomena not applicable to the interaction of gamma and x-radiation with matter. Reflection, refraction, and transmission pertain to optical effects