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Revision:X-RaysTSR Wiki > Study Help > Subjects and Revision > Revision Notes > Physics > X-Rays Wavelength: 10-11m to 10-9m
SourcesThe bombardment of targets of heavy atoms (typically tungsten) by fast moving electrons causes energy levels in the target to change. When the target atoms' excited electrons drop back to their original level, they release fixed quanta of electromagnetic energy. (This is called the photoelectric effect). Basically, X-rays are produced whenever electrons are rapidly brought to rest by matter, however only < 0.5% of the electron's kinetic energy gets converted into these X-rays.
DetectionPhotographic plates, fluorescence of certain chemicals (eg, barium platnocyanide), ionization chambers (similar to Geiger counters but at a higher pressure).
UsesThe most well known use of X-rays is for medical scans. These are commonly known as “x-rays”, this, of course, is incorrect since this is the name of the wave not the method. The method is really called radiography or X-ray photography. This form of detection uses it's fluorescence property.
NotesThere is no difference between the longest wavelength gamma rays and shortest wavelength X- rays (10-11m). Which name is used usually depends on source and use. X-rays were so called because at first their nature was unknown, for some reason the name stuck once it's nature had been discovered. Short wavelength X-rays are called hard X-rays, long wavelength X-rays are called soft X-rays. X-rays -- just like all electromagnetic rays -- are not deflected by electric or magnetic fields, and it can thus be deduced that they do not carry a charge.
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