Which statement about coherent scattering is true?

Which statement about coherent scattering is true?

• A. It involves interaction with the whole atom
• B. It involves interaction with the atomic nucleus
• C. It results in ionization
• D. It always changes the photon energy

Answer: (C)

Coherent scattering is Rayleigh scattering, where the photon scatters elastically off the bound electrons as a single, collective interaction with the entire atom. The atom remains in its ground state, so there is no ionization and essentially no change in the photon’s energy. Because the process is elastic, the scattered photon keeps the same energy (wavelength) as the incident photon, aside from tiny, practically negligible differences. This is why the statement about interacting with the whole atom is the true one: the interaction is with the atom as a whole, not specifically with the nucleus, and it does not ionize or require a change in photon energy.

Coherent scattering is Rayleigh scattering, where the photon scatters elastically off the bound electrons as a single, collective interaction with the entire atom. The atom remains in its ground state, so there is no ionization and essentially no change in the photon’s energy. Because the process is elastic, the scattered photon keeps the same energy (wavelength) as the incident photon, aside from tiny, practically negligible differences. This is why the statement about interacting with the whole atom is the true one: the interaction is with the atom as a whole, not specifically with the nucleus, and it does not ionize or require a change in photon energy.