What are the three primary types of ionizing radiation?

The three primary types of ionizing radiation are alpha particles, beta particles, and gamma rays. Alpha particles are composed of two protons and two neutrons, giving them a positive charge and a relatively large mass compared to other types of radiation. They have limited penetrating power and can be stopped by a sheet of paper or even the outer layer of human skin.

Beta particles are high-energy, high-speed electrons or positrons that are emitted from a decaying atomic nucleus. They have greater penetrating power than alpha particles, requiring materials like plastic or glass to effectively shield against them.

Gamma rays are a form of electromagnetic radiation, similar to X-rays but with higher energy. They are deeply penetrating and can pass through the human body and most materials. Effective shielding against gamma rays typically requires dense materials such as lead or several centimeters of concrete.

The other options include types of radiation or particles that do not fall under the category of ionizing radiation. Ultraviolet rays, for instance, are a form of non-ionizing radiation, and microwave radiation is also non-ionizing. Neutrons, protons, and electrons pertain to fundamental particles in atomic physics rather than types of radiation commonly encountered in the context of radiation protection.