How much of a 75-kVp beam is attenuated by a 0.5-mm apron?

The attenuation of a 75-kVp beam by a 0.5-mm lead apron is understood in the context of how much the beam's intensity is reduced as it passes through the material. In radiation protection, the materials used, such as lead in aprons, have specific attenuation properties that correspond to their thickness and the energy of the x-ray beam.

For a 75-kVp beam, a 0.5-mm thickness of lead would typically attenuate approximately 88% of the beam's intensity. This number reflects the ability of lead to absorb x-rays efficiently due to its high atomic number and density, which makes it particularly effective in providing radiation protection.

This degree of attenuation is significant for ensuring that personnel are protected from unnecessary radiation exposure during procedures that involve x-rays. Understanding the amount of radiation that can penetrate different thicknesses of protective materials is crucial for developing protocols to minimize exposure in medical and dental settings.

In this case, the estimation of 88% attenuation aligns with the empirical data on lead aprons, making it the correct answer.