What are X-rays?
X-rays are a form of radiation that can pass through solid and semi-solid substances. In carefully controlled doses, they can be used to capture images of the body's internal structures.
How X-rays work
X-rays are a type of radiation. Light and X-rays are similar sources of energy. However, light has a much lower frequency than X-rays and is absorbed by your skin. X-rays have a higher frequency and pass through the human body. As X-rays pass through the body, energy particles in them (called photons) are absorbed at different rates. This pattern shows up on the X-ray images. The parts of your body that are made up of dense material, such as your bones, show up as clear white areas on an X-ray image. The parts of your body that are made of softer material, such as your heart and lungs, show up as darker areas.
X-rays are manufactured by an x-ray machine. A hot cathode emits electrons that are attracted to a tungsten anode. When the fast-moving electrons hit the metal target, most of their kinetic energy is transferred to heat but some is transferred to x-rays.
This machine allows the energy and intensity of the x-rays to be controlled. Gamma rays, on the other hand, are given out by radioactive materials. This process is totally random and so cannot be controlled as easily as x-rays.
X-ray production whenever electrons of high energy strike a heavy metal target, like tungsten or copper. When electrons hit this material, some of the electrons will approach the nucleus of the metal atoms where they are deflected because of there opposite charges (electrons are negative and the nucleus is positive, so the electrons are attracted to the nucleus). This deflection causes the energy of the electron to decrease, and this decrease in energy then results in forming an x-ray. Half value thickness
The thickness of absorber needed to reduce the corrected count rate to half its original value is called the half-value thickness. Uses of x...
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