Which shielding material is adequate for stopping beta particles?

• A. Glass
• B. Paper
• C. Aluminum foil
• D. Lead

Answer: (C)

The choice of aluminum foil as an adequate shielding material for stopping beta particles is based on the properties of beta radiation and the effectiveness of the materials in absorbing or obstructing it. Beta particles are charged particles (electrons or positrons) that have a moderate range of penetration compared to alpha particles.

Aluminum foil is effective because it is thin enough to stop fast-moving beta particles due to the material's atomic mass and density. Even a few millimeters of aluminum can significantly reduce the intensity of beta radiation, making it a practical choice for shielding in various applications, such as in laboratories and medical settings where beta emitters might be handled.

In contrast, materials like glass or paper, while they can provide some level of protection, are typically less effective than aluminum at stopping beta particles. Glass may absorb some beta radiation, but it is not as effective as aluminum, especially with higher-energy beta emissions. Paper can stop low-energy beta particles but may not provide adequate shielding for beta emissions of higher energy. Lead, while effective against gamma radiation and higher energy particles, is not necessary for beta particles, as thinner and lighter materials like aluminum serve the purpose more efficiently.

Thus, the use of aluminum foil for shielding against beta radiation is a well-accepted practice based