A petahertz (symbol PHz) is a measure of frequency equal to a quadrillion hertz or a thousand terahertz. Sine waves of various frequencies; the lower waves have higher frequencies than those above. ... (Redirected from 1 E15) This list compares various sizes of positive numbers, including counts of things, dimensionless numbers and probabilities. ... The hertz (symbol Hz) is the SI unit of frequency. ... A terahertz (THz) is 1012 hertz or a thousand gigahertz, a measure of frequency. ...

In the electromagnetic spectrum, the low end of the petahertz range includes infrared light, visible light (highest sensitivity of the human eye is at 0.54 PHz), and ultraviolet light, while the upper range includes X-rays and gamma rays. The electromagnetic spectrum encompasses all possible wavelengths of electromagnetic radiation. ... Image of a small dog taken in mid-infrared (thermal) light (false color) Infrared (IR) radiation is electromagnetic radiation of a wavelength longer than visible light, but shorter than microwave radiation. ... The optical spectrum (light or visible spectrum) is the portion of the electromagnetic spectrum that is visible to the human eye. ... See: Sensitivity (electronics) Sensitivity (human) Sensitivity (tests) For sensitivity in finance, see beta coefficient This is a disambiguation page — a navigational aid which lists other pages that might otherwise share the same title. ... Binomial name Homo sapiens Linnaeus, 1758 Subspecies Homo sapiens idaltu (extinct) Homo sapiens sapiens Human beings define themselves in biological, social, and spiritual terms. ... An eye is an organ that detects light. ... Ultraviolet (UV) radiation is electromagnetic radiation of a wavelength shorter than that of the visible region, but longer than that of soft X-rays. ... In the NATO phonetic alphabet, X-ray represents the letter X. An X-ray picture (radiograph) taken by Röntgen An X-ray is a form of electromagnetic radiation with a wavelength approximately in the range of 5 pm to 10 nanometers (corresponding to frequencies in the range 30 PHz... This article is about electromagnetic radiation. ...

See also SI prefix. An SI prefix is a prefix which can be applied to any unit of the International System of Units (SI) to give subdivisions and multiples of that unit. ...

terahertz << petahertz << exahertz A terahertz (THz) is 1012 hertz or a thousand gigahertz, a measure of frequency. ... Exahertz is a unit for measuring frequency equal to 1000 petahertz or one quintillion hertz. ...