Final answer:
The inverse square law does not directly apply to particulate radiation such as alpha and beta particles. These particles have a different range and ionization capability due to their mass and charge. Alpha particles are easily stopped and highly ionizing, beta particles penetrate further, and gamma rays, which do follow the inverse square law, can penetrate deeply and require dense materials for shielding.
Step-by-step explanation:
The inverse square law primarily applies to point sources of radiation that spread out uniformly in all directions, such as gamma rays, rather than particulate forms of radiation like alpha and beta particles. This is because the inverse square law is derived from the concept of a spreading wavefront or radiation sphere, which isn't typically how particulate radiation behaves. Alpha particles, with a charge of +2e and a relatively large mass, have a short range and are strongly ionizing. Beta particles, with a charge of -e, penetrate farther than alpha particles due to their smaller mass and charge. Gamma rays, being chargeless and massless electromagnetic waves, have the greatest range and penetrate materials much more deeply.
Alpha particles can be stopped by a thin barrier such as paper or skin cells and are dangerous when ingested or inhaled. Beta particles can pass through a hand or thin materials but are stopped by a thin layer of metal. In contrast, gamma rays are highly penetrative and require dense materials like lead for effective shielding. The ability to produce ionization varies greatly among these types of emissions, with alpha particles having significantly higher ionizing power compared to gamma rays.