Which of the following materials is most effective at shielding X-rays?

Question

Question

Answer 1

Correct Answer: Lead

Rationale:

Lead is highly effective at shielding X-rays due to its high atomic number and density. These properties enable lead to absorb and scatter X-ray photons, preventing them from passing through.
The effectiveness of a material in shielding against X-rays is determined by its ability to attenuate the radiation, which is a function of both its density and atomic number. Lead's high atomic number (82) provides a large number of electrons, which interact with X-ray photons to reduce their energy.
Lead is commonly used in various applications such as protective aprons, shields, and barriers in medical and dental radiology, as well as in industrial radiography.

Explanation of Other Options:

Aluminum

Rationale: Aluminum has a lower atomic number (13) and density compared to lead. While it can provide some shielding against X-rays, it is not as effective as lead, especially at higher energy levels.

Plastic

Rationale: Plastic has a very low atomic number and density, making it ineffective at shielding X-rays. It does not provide significant attenuation of X-ray photons, making it unsuitable for protective purposes.

Steel

Rationale: Steel has a higher density than aluminum and plastic but a lower atomic number (around 26) than lead. While it can provide some level of X-ray shielding, it is not as effective as lead. Additionally, steel is harder and less malleable, which can make it less practical for certain shielding applications.

Conclusion:

Among the given options, lead is the most effective material for shielding against X-rays due to its high atomic number and density. These properties enable it to attenuate X-ray radiation efficiently, making it the preferred choice in medical, dental, and industrial radiographic protection.