The document discusses X-rays, including their history, generation, applications, and challenges. It provides details on how Wilhelm Roentgen accidentally discovered X-rays in 1895 while experimenting with electron beams. X-rays are generated when high-energy electrons strike an anode target, releasing 1% of their kinetic energy as X-rays. X-rays are used widely in medicine for diagnostic imaging like bone structure imaging, as well as in security screening, scientific research, and archaeology. However, diagnostic X-ray radiation poses cancer and tumor risks if overexposed.
3. INTRODUCTION:
X-rays are electromagnetic waves but they are more
energetic so they can penetrate many materials.
When the X-rays hit the film, they expose it just as
light would.
Since bone, fat, muscle, tumours and other masses
all absorb X-rays at different levels, the image on the
film lets you see different (distinct) structures inside
the body because of the different levels of exposure
on the film.
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4. History of X-ray:
X-ray technology was invented completely by
accident. In
1895, a German physicist “Wilhelm Roentgen”
made the discovery while experimenting with
electron beams in a gas discharge tube.
He noticed that a fluorescent screen in his lab
started to glow when the electron beam was
turned on.
fluorescent material normally glows in reaction to
electromagnetic radiation, but Roentgen's tube
was surrounded by heavy black cardboard.4
5. Roentgen placed various objects between the
tube and the screen, and the screen still glowed.
Finally, he put his hand in front of the tube, and
saw the outline of his bones projected onto the
fluorescent screen.
The new rays he temporarily termed "X-rays",
using the mathematical designation ("X") for
something unknown.
Immediately after discovering X-rays themselves,
he had discovered their most beneficial
application.
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6. Generation of X-ray:
The system is designed to provide a large number
of electron at cathode with high kinetic energy
focused to a small target at anode.
The cathode is heated to release a large number of
electons by a process known as thermionic
emission.
Electrons emitted from the cathode are accelerated
by high voltage towards anode.
The whole process needs to be conducted in a
high vaccum.
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7. When the high energy electrons strike the anode they
release their energy in the form of X-ray.
But 99% of the electron kinetic energy is converted
into heat and only 1% is converted into X-ray.
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8. Application of X-rays:
X-rays are used in medicine like identifying bone
structures ,dental radiography, mammography,
Radiotherapy etc.
X-ray machines are used in airports and various
stations to check luggage etc.
In Science x-rays are used to analyze the arrangement
of atoms in many kinds of substances particularly
crystals.
Archaeologists used X-rays to examine ancient objects
covered by a crust of dirt.
Used in research involving quantum mechanics theory
crystallography and cosmology.
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10. Working of X-rays:
X-rays are able to penetrate through materials of light
atoms like flesh. The heavier atoms like metal absorb
them.
A filter near the x-ray source blocks the low energy
rays so only the high energy rays pass through a
patient toward a sheet of film.
Calcium in bones is considered a type of metal so
they absorbs X-ray photons. when photographic film
is placed on the body, this allows the technician to
take the picture.
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11. Challenges:
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Diagnostic X-rays radiation can cause cell
mutations that may lead to cancer and tumours.
Thyroid glands, which are the primary glands of
metabolism and energy, are also known victims of
x-rays.
Multiple X-rays have been linked with multiple
myeloma – a form of bone marrow cancer.
Old X-ray equipment gives off 20 to 30 times as
high a dose of radiation as new one.