Medical Physics

X-rays and ultrasounds can both travel through a medium, but only x-rays can travel through a vacuum, this is because it doesn’t involve particles. Ultrasounds are not ionising and don’t damage or kill cells, but x-rays are the opposite, this is because they have enough energy to knock electrons from molecules, ultrasounds don’t have this energy. X-rays are transverse and ultrasounds are longitudinal.

Photographic film is exposed to x-rays so it can be viewed in visible light without affecting the image. X-rays are absorbed by metal and bone, so these leave white marks on the film. Healthy tissue transmits x-rays. CT scans produce a 3D x-ray by taking a number of x-rays from different positions and angles. CCDs convert light into electrical signals, which can be stored in a computer’s memory.

Radio therapy…