Which of the following is NOT a contributor to attenuation?

• A. Diffraction
• B. Reflection
• C. Absorption
• D. Scattering

Answer: (A)

Attenuation refers to the loss of a wave’s energy as it travels through a medium, due to mechanisms that remove or redirect energy from the forward path. Absorption converts wave energy into heat, reducing forward intensity. Scattering sends energy in directions away from the original beam, also lowering what continues forward. Reflection takes energy away from the transmitted beam by bouncing it back toward the source or in other directions. Diffraction, by contrast, is the bending and spreading of waves around obstacles or through openings; it redistributes energy rather than removing it. So it does not inherently reduce the total energy in the beam, making diffraction not a contributor to attenuation.