The Physics behind X-ray imaging

Well done to Kayleigh for their creative submission explores the physics behind x-rays. Take a look at their cover letter below:

As a child, I always wondered how X-rays could take photos of my bones so clearly even though they were covered by my skin. So, in my project I cover and concentrate on why X-ray images only show bones, and certain things inside my body and what makes them so special you can see them. To explain this I use physics and I have displayed my research in the form of a digital animation using diagrams and pictures (along with my voice) to make it easier to understand. The answer to “How do X-rays see our bones but not other things?” is density. It affects the ability for rays to pass through different things. Our skin, muscles and other soft tissues are less dense (how tightly a material is packed together) which means they are darker/ “invisible” on the x-ray images due to the fact this makes the beams easier to pass through and go to the detector on the other side of the X-ray machine. Whereas bones and foreign objects (for example) are more dense meaning they show up brighter or, for some objects, bright white.