Which radiation is the most penetrating and can pass through the body?

Which radiation is the most penetrating and can pass through the body?

• A. Alpha radiation
• B. Gamma radiation
• C. Neutron radiation
• D. Beta radiation

Answer: (B)

Penetration power varies with the type of radiation because of mass, charge, and how they interact with matter. Alpha particles are heavy and carry a positive charge, so they lose energy quickly and are stopped by a sheet of paper or the outer layer of skin. Beta particles are lighter and still charged, so they travel farther than alpha but are halted by a few millimeters of plastic or thin metal. Neutrons have no charge, so their interaction with matter is different and depends on energy; they can be quite penetrating but require specific materials to slow or capture them. Gamma rays are high-energy photons with no mass or charge, so they pass through the body with relatively little attenuation and demand dense shielding like lead or thick concrete to reduce their impact. Because of this extensive ability to pass through the body, gamma radiation is the most penetrating.

Penetration power varies with the type of radiation because of mass, charge, and how they interact with matter. Alpha particles are heavy and carry a positive charge, so they lose energy quickly and are stopped by a sheet of paper or the outer layer of skin. Beta particles are lighter and still charged, so they travel farther than alpha but are halted by a few millimeters of plastic or thin metal. Neutrons have no charge, so their interaction with matter is different and depends on energy; they can be quite penetrating but require specific materials to slow or capture them. Gamma rays are high-energy photons with no mass or charge, so they pass through the body with relatively little attenuation and demand dense shielding like lead or thick concrete to reduce their impact. Because of this extensive ability to pass through the body, gamma radiation is the most penetrating.