X-rays, or very rarely, X-rays are transmissive types of high-energy electromagnetic radiation. Most X-ray wavelengths range from 10 picometers to 10 nanometers, which corresponds to frequencies in the range of 30 petahertz to 30 exahertz (30 x 1015 Hz to 30 x 1018 Hz) and energies from 145 eV to 124 keV. .. range. security x-ray
X-rays have shorter wavelengths than UV light and are usually longer than gamma rays. In many languages, X-rays are called X-rays, named after the German scientist Wilhelm Conrad Roentgen, who discovered X-rays on November 8, 1895. [1] He called it X-rays and pointed to an unknown type of radiation. [2] X-ray English spelling includes x-rays, x-rays, and x-ray variants.
[3] The most well-known use of x-rays is to check for fractures (fractures), but x-rays are also used in other ways. For example, a chest x-ray can detect pneumonia. Mammograms use x-rays to look for breast cancer. Prior to its discovery in 1895, X-rays were just one type of unidentified radiation emitted from experimental discharge tubes.
They were noted by scientists studying cathode rays produced by such tubes, which are the first high-energy electron beams observed in 1869. Many of the early Crookes tubes (invented around 1875) definitely emitted X-rays as early researchers noticed the effects they caused, as detailed below. The Crookes tube generated free electrons by ionizing the residual air in the tube at a high DC voltage of a few kilovolts to 100 kV. This voltage accelerated the electrons coming from the cathode to a high enough velocity that they created Xrays when they struck the anode or the glass wall of the tube.[4]
The earliest experimenter thought to have (unknowingly) produced Xrays was William Morgan. In 1785, he presented a paper to the Royal Society of London describing the effects of passing electrical currents through a partially evacuated glass tube, producing a glow created by Xrays.[5][6] This work was further explored by Humphry Davy and his assistant Michael Faraday.
When Stanford University physics professor Fernando Sanford created his "electric photography", he also unknowingly generated and detected Xrays. From 1886 to 1888, he had studied in the Hermann von Helmholtz laboratory in Berlin, where he became familiar with the cathode rays generated in vacuum tubes when a voltage was applied across separate electrodes, as previously studied by Heinrich Hertz and Philipp Lenard.
His letter of January 6, 1893 (describing his discovery as "electric photography") to The Physical Review was duly published and an article entitled Without Lens or Light, Photographs Taken With Plate and Object in Darkness appeared in the San Francisco Examiner.[7]
Starting in 1888, Philipp Lenard conducted experiments to see whether cathode rays could pass out of the Crookes tube into the air. He created a Crookes tube with a "window" at the end of the thin aluminum facing the cathode so that the cathode ray hits the cathode (later called the "Lenard tube"). Read more...
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