| slovo | definícia |
X rays
(gcide) | Rontgen ray \R["o]ntgen ray\, Roentgen ray \Roentgen ray\ [see
R["o]ntgen.] (Physics)
An X-ray; originally, the term was applied to any of the
rays produced when cathode rays strike upon surface of a
solid (as the wall of the vacuum tube), but now it refers
specifically to electromagnetic radiation having wavelengths
from 10^-3 nm to 10 nm, immediately below ultraviolet
radiation on the wavelength scale. R["o]ntgen rays are noted
for their penetration of opaque substances, as wood and
flesh, their action on photographic plates, and their
fluorescent effects. They were called X rays by their
discoverer, W. K. R["o]ntgen. They are one of the forms of
ionizing radiation, which can have damaging effects on living
cells. They also ionize gases, but cannot be reflected, or
polarized, or deflected by a magnetic field. They are used in
examining opaque objects, especially in medicine for
visualizing organs and other objects inside the human body,
as for locating fractures or bullets, and examining internal
organs for abnormalities.
[Webster 1913 Suppl. +PJC] |
X rays
(gcide) | X ray \X ray\, X-ray \X-ray\([e^]ks"r[=a]`), n. [so called by
its discoverer because of its enigmatical character, x being
an algebraic symbol for an unknown quantity.] (Physics)
Originally, any of the rays produced when cathode rays strike
upon surface of a solid (as a copper target or the wall of
the vacuum tube); now defined as electromagnetic radiation
with a wavelength of 0.1 to 10 nanometers. X-rays are noted
for their penetration of many opaque substances, as wood and
flesh, their action on photographic plates, and their
fluorescent effects. They were called X rays by their
discoverer, W. K. R["o]ntgen, but were also referred to for
some time as Roentgen rays. The term X-ray has become the
most common designation. They also ionize gases, but cannot
be reflected, or polarized, or deflected by a magnetic field.
They are used in examining objects opaque to visible light,
as for imaging bones or other structures inside the human
body, and for detecting flaws in metal objects, such as in
welds.
[Webster 1913 Suppl. +PJC] X ray |
| |