An X-ray is a form of electromagnetic radiation. Their wavelength is smaller the UV rays and they are therefore invisible to the human eye. Due to this small wavelength, x-rays are able to pass through solid objects. Their ability to penetrate solid objects depends on how dense the material of the object is.
Why does the X-Ray photograph only show bones?
The human body is made up of bones, muscle, skin, tissue and muscles. All these have varying densities where bones are the most tightly packed. When you pass an x-ray through a body, the bones are the only part through which the x-rays are not able to pass. If you place photographic paper on the other side of your body, only those rays which have passed through the body will turn the paper dark. This is why bones show up as white spaces on an x-ray and how doctors can tell if you have an injury to your skeletal structure.
An abdominal X-Ray
So how can we take an x-ray of something like the stomach, if the rays will just pass through them? You will have to drink a special liquid that will change the density of the stomach. This liquid will slow down the x-rays. X-rays are even used to photograph old objects like artifacts and paintings, because we are able to see details, that have been lost by time and corrosion.
How safe are X-Rays?
X-rays are not to be fooled around with. Too much exposure to these tiny waves could result in serious damage to your body. Can you find out what kind of damage x-rays can do to your body over a long period of time?
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