X-Rays are really very similar to light rays except X-Rays can pass through objects that light cannot. Seems like magic – doesn’t it? Wilhelm C. Roentgen, the mad scientist that discovered x-rays in 1895, was a little stunned too when he first stumbled across the phenomena. He was experimenting in his lab one day when he decided to put a glass tube in a box. The glass tube had wires running through it that would carry an electric current. He flipped the switch and almost fell over when the thing started emitting a strange green light that filled the room. He reached over and really was shocked to see the light penetrated through his flesh and he could actually see the outlines of the bones in his hand on a film he had taped to a wall. He knew they were some sort of rays but since he had no idea how they worked he named them X-Rays (with the X showing that they were unknown).
X-Rays are like light rays but they have more energy than light so they can go right through stuff (they have a shorter wavelength too). Light can’t pass through your body or a suitcase, but x-rays can.
An x-ray picture works similar to a picture taken by a regular camera. With a regular camera, the light bounces off whatever you’re taking a picture of and exposes the film producing an image. X-rays do the same thing except we take advantage of the fact that x-rays can’t quite pass through everything. If you x-ray your hand, the x-rays pass right through the flesh but bounce back off of the bone and expose the film so than only an image of the bone is made.
X-rays have a lot of uses. We’re most familiar with doctors and dentists using them to x-ray our bodies but they’re also used in airports to examine the contents of luggage without actually opening them. Big factories use them to examine machines and parts for very small fractures or cracks that you might not be able to see easily.