Helices

Physics-p3 1.1 X-Rays Part of the electromagnetic spectrum; they have a high frequency and short wavelength. X-rays are used to form images of bone on photographic film to check for fractures and dental fractures. This is done because they are transmitted by healthy tissue and absorbed by bone. X-rays affect photographic film in the same way as light. Charge-coupled devices (CCDs) are used to form electronic images of the body. X-rays are used to make images and CT scans (cross sections through the body). They are also used to destroy tumors at or near the body surface. Precautions must be taken when using X-rays as they cause ionization and can damage living tissue. Workers should wear film badges (to monitor exposure) and use lead screens to shield them when possible.