What type of radiation typically has the greatest penetrating power?

Gamma rays possess the greatest penetrating power among the types of radiation listed. This is due to their nature as electromagnetic radiation with very high frequency and energy. Gamma rays are not charged and therefore do not interact as readily with matter compared to charged particles like alpha and beta particles.

Alpha particles, being heavy and positively charged, are heavily impeded by even a few centimeters of air or a sheet of paper. Beta particles, which are lighter and negatively charged, have better penetrating ability than alpha particles but can still be stopped by materials like plastic or glass. Neutrons can penetrate materials effectively as they are neutral, but they are generally less penetrating than gamma rays. Gamma radiation, with its significant energy and wave nature, can pass through various materials including human tissue, concrete, and lead, making it extremely penetrating in comparison to the other types of radiation.