X-rays definition
X-rays are electromagnetic radiation that differentially penetrates structures within the body and creates images of these structures on photographic film or a fluorescent screen.
Most X-rays have a wavelength ranging from (0.01 to 10) nanometers, and energies in the range 100 eV to 100 keV. X-ray wavelengths are shorter than those of UV rays and typically longer than those of gamma rays. In many languages, X-radiation is referred to with terms meaning R?ntgen radiation, after Wilhelm R?ntgen, who is usually credited as its discoverer, and who had named it X-radiation to signify an unknown type of radiation.
**Unit of measurement in x-ray region is ? and nm. (1 ? = 10-10 m, 1 nm = 10 ? = 10-9 m)
1)Electromagnetic radiation can be considered as wave motion in accordance with classical theory.
E = A exp(x/? –?)
A : amplitude of the wave. , E: electric field. , ?: wavelength.
?: frequency. , (? = ?t).
According to the quantum theory: electromagnetic radiation can also be considered as a particles called photons. Each photon has associated with it an amount of energy:
E = h?
Where: h = 6.63×10-34 Js. , ?: frequency.
المادة المعروضة اعلاه هي مدخل الى المحاضرة المرفوعة بواسطة استاذ(ة) المادة . وقد تبدو لك غير متكاملة . حيث يضع استاذ المادة في بعض الاحيان فقط الجزء الاول من المحاضرة من اجل الاطلاع على ما ستقوم بتحميله لاحقا . في نظام التعليم الالكتروني نوفر هذه الخدمة لكي نبقيك على اطلاع حول محتوى الملف الذي ستقوم بتحميله .
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