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  2. Ultraviolet - Wikipedia

    en.wikipedia.org/wiki/Ultraviolet

    Ultraviolet radiation, also known as simply UV, is electromagnetic radiation of wavelengths of 10–400 nanometers, shorter than that of visible light, but longer than X-rays. UV radiation is present in sunlight , and constitutes about 10% of the total electromagnetic radiation output from the Sun.

  3. N-ray - Wikipedia

    en.wikipedia.org/wiki/N-ray

    The N-ray affair occurred shortly after a series of major breakthroughs in experimental physics. Victor Schumann discovered vacuum ultraviolet radiation in 1893, Wilhelm Röntgen discovered X-rays in 1895, Henri Becquerel discovered radioactivity in 1896, and, in 1897, J. J. Thomson discovered electrons, showing that they were the constituents of cathode rays. [1]

  4. Ultraviolet catastrophe - Wikipedia

    en.wikipedia.org/wiki/Ultraviolet_catastrophe

    The ultraviolet catastrophe, also called the Rayleigh–Jeans catastrophe, was the prediction of late 19th century and early 20th century classical physics that an ideal black body at thermal equilibrium would emit an unbounded quantity of energy as wavelength decreased into the ultraviolet range.

  5. Ultraviolet index - Wikipedia

    en.wikipedia.org/wiki/Ultraviolet_index

    The ultraviolet index, or UV index, is an international standard measurement of the strength of the sunburn-producing ultraviolet (UV) radiation at a particular place and time. It is primarily used in daily and hourly forecasts aimed at the general public.

  6. Ultraviolet photoelectron spectroscopy - Wikipedia

    en.wikipedia.org/wiki/Ultraviolet_photoelectron...

    If Albert Einstein's photoelectric law is applied to a free molecule, the kinetic energy of an emitted photoelectron is given by =, where h is the Planck constant, ν is the frequency of the ionizing light, and I is an ionization energy for the formation of a singly charged ion in either the ground state or an excited state.

  7. Golden age of physics - Wikipedia

    en.wikipedia.org/wiki/Golden_age_of_physics

    Solvay Conference of 1927, with prominent physicists such as Albert Einstein, Marie Curie, Erwin Schrödinger and Paul Dirac.. A golden age of physics appears to have been delineated for certain periods of progress in the physics sciences, and this includes the previous and current developments of cosmology and astronomy.

  8. Indoor tanning - Wikipedia

    en.wikipedia.org/wiki/Indoor_tanning

    Indoor tanning involves using a device that emits ultraviolet radiation to produce a cosmetic tan. [a] Typically found in tanning salons, gyms, spas, hotels, and sporting facilities, and less often in private residences, the most common device is a horizontal tanning bed, also known as a sunbed or solarium. Vertical devices are known as tanning ...

  9. UV filter - Wikipedia

    en.wikipedia.org/wiki/UV_filter

    UV filters were used to filter out shorter ultraviolet wavelengths while remaining transparent to visible light. However, the modern-day photographic film and digital cameras are less sensitive to UV wavelengths. UV filters are sometimes referred to as L37 or L39 filters, depending on the wavelengths of light they filter out.