Question: Can you tell me more about how x-rays work

Emily Cook answered on 15 Mar 2010:

X-rays are produces by machines that accelerate electrons and smash them into metal targets, giving off x-rays.
X-rays are like light, but have a much higher energy so, while light all is absorbed by our skin, muscle and bones, x-rays can get through. Not all of them get through though. X-rays are most strongly absorbed by dense materials and materials with high atomic numbers (like lead). Most of the tissues in our bodies, like muscle and fat, are made from carbon, oxygem and hydrogen, all things with very low atominc numbers. Our bones have calcuim in them which is denser and has a higher atomic number (20) so bones absorb more x-rays. When an x-ray picture (call a radiograph) is taken you get a ‘shadow picture’ of what abosrbed the x-rays. Where lots are have passed through the body the film is blacked alot. where not many get through the film stays white, so bones look lighter and breaks show up as darker shadows.