Why is lead used as a shield against X-rays?

Lead is used as a shield against X-rays because it is a dense material that can absorb radiation.

X-rays are a type of electromagnetic radiation that can penetrate through materials and cause damage to living tissues. To protect people from the harmful effects of X-rays, shields made of dense materials are used. Lead is a popular choice for X-ray shielding because it is a heavy metal with a high atomic number, which means it has a large number of protons in its nucleus. This makes lead an effective absorber of X-rays.

When X-rays pass through a material, they can interact with the atoms in the material and cause ionization. This ionization can lead to the formation of free radicals, which can damage cells and DNA. However, when X-rays pass through lead, the high atomic number of the lead atoms causes the X-rays to interact more strongly with the lead atoms, leading to a higher chance of absorption. This means that less radiation reaches the other side of the lead shield, reducing the risk of harm to people on the other side.

In addition to its high atomic number, lead is also a dense material, which means that it can pack a large number of atoms into a small space. This makes lead shields relatively thin and lightweight, while still providing effective protection against X-rays. However, it is important to note that lead is not a perfect shield against X-rays, and other materials such as concrete and steel may also be used depending on the specific application.