X-Rays are really quite amazing when you really think about it. I mean, come
guys, it lets you see right through things! Image how much fun it would be
to have x-ray vision. When dad left for work you could snicker about his polka-dotted
boxer shorts. At Wal Mart you could look at stuff without having to sneak
open the box. Heck, when the kids played 'guess what I'm holding behind my
back' you'd win every time!
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 starting 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 similar to 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.
A 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.