Which material is known as one of the best absorbers of x-rays?

Lead is known to be one of the best absorbers of x-rays due to its high atomic number and density. The effectiveness of a material in shielding against x-rays primarily depends on these two properties. When x-ray photons encounter lead, they are more likely to interact with the lead atoms rather than pass through, which reduces the exposure to radiation behind the lead barrier. This characteristic makes lead an essential material for protective clothing, such as lead aprons used in medical settings, and for constructing barriers in diagnostic imaging and radiation therapy facilities.

Other materials listed, such as aluminum and glass, are not as effective because they have lower atomic numbers and less density, resulting in less interaction with x-ray photons. Plastic, while lightweight and less expensive, also does not provide significant shielding compared to lead. Thus, lead is the preferred choice for maximizing x-ray absorption and minimizing radiation exposure.