What does ultraviolet mean in physics?
What does ultraviolet mean in physics?
Ultraviolet radiation is electromagnetic radiation or light having a wavelength greater than 100 nm but less than 400 nm. The word “ultraviolet” means “beyond violet”. Ultraviolet radiation was discovered by the German physicist Johann Wilhelm Ritter in 1801.
What is ultraviolet light energy?
Ultraviolet radiation (UV) is a type of radiant energy, much like the light we see, but with a smaller wavelength and higher energy. It is defined as the light in the spectrum of wavelengths between 40-400 nanometers. The electromagnetic spectrum. UV lies between x-ray and visible light.
What is the mode of action of ultraviolet light?
UV radiation can mediate damage via two different mechanisms: (a) direct absorption of the incident light by the cellular components, resulting in excited state formation and subsequent chemical reaction, and (b) photosensitization mechanisms, where the light is absorbed by endogenous (or exogenous) sensitizers that …
Does ultraviolet light carry energy?
Ultraviolet radiation has shorter waves than blue or violet light, and thus oscillates more rapidly and carries more energy per photon than visible light does.
What is ultraviolet waves and its uses?
Ultraviolet rays can be used to kill microbes. Hospitals use UV lamps to sterilise surgical equipment and the air in operating theatres. Suitable doses of Ultraviolet rays cause the body to produce vitamin D, and this is used by doctors to treat vitamin D deficiency and some skin disorders.
What is UV light wavelength?
Ultraviolet radiation lies between wavelengths of about 400 nanometres (1 nanometre [nm] is 10−9 metre) on the visible-light side and about 10 nm on the X-ray side, though some authorities extend the short-wavelength limit to 4 nm.
Why is ultraviolet called ultraviolet?
“Ultraviolet” means “beyond violet” (from Latin ultra, “beyond”), violet being the color of the highest frequencies of visible light. Ultraviolet has a higher frequency (thus a shorter wavelength) than violet light.
How are ultraviolet waves created?
Ultraviolet radiation is produced by high-temperature surfaces, such as the Sun, in a continuous spectrum and by atomic excitation in a gaseous discharge tube as a discrete spectrum of wavelengths. Of the ultraviolet that does reach Earth’s surface, almost 99 percent is UVA radiation.
What are ultraviolet used for?
UV radiation is widely used in industrial processes and in medical and dental practices for a variety of purposes, such as killing bacteria, creating fluorescent effects, curing inks and resins, phototherapy and suntanning. Different UV wavelengths and intensities are used for different purposes.
What type of mutation occurs from UV radiation?
A genetic mutation caused by ultraviolet light is likely the driving force behind millions of human skin cancers, according to researchers at the Stanford University School of Medicine. The mutation occurs in a gene called KNSTRN, which is involved in helping cells divide their DNA equally during cell division.
How does ultraviolet waves transfer energy?
Ultraviolet radiation is absorbed by molecules and is known as nonionizing radiation. Another theory used in reference to the electromagnetic spectrum is the quantum theory. In order to explain energy transfer, a bit of energy called a photon was theorized.
