A microsecond is a unit of

time Time is the continued sequence of existence and events that occurs in an apparently irreversible succession from the past, through the present, into the future. It is a component quantity of various measurements used to sequence events, ...

in the International System of Units (SI) equal to one

millionth One millionth is equal to 0.000 001, or 1 x 10−6 in scientific notation. It is the reciprocal of a million, and can be also written as . Units using this fraction can be indicated using the prefix "micro-" from Greek, meaning "small". Numbers o ...

(0.000001 or 10⁻⁶ or ) of a second. Its symbol is μs, sometimes simplified to us when

Unicode Unicode, formally The Unicode Standard,The formal version reference is is an information technology standard for the consistent encoding, representation, and handling of text expressed in most of the world's writing systems. The standard, wh ...

is not available. A microsecond is equal to 1000

nanosecond A nanosecond (ns) is a unit of time in the International System of Units (SI) equal to one billionth of a second, that is, of a second, or 10 seconds. The term combines the SI prefix ''nano-'' indicating a 1 billionth submultiple of an SI unit ( ...

s or of a millisecond. Because the next SI prefix is 1000 times larger, measurements of 10⁻⁵ and 10⁻⁴ seconds are typically expressed as tens or hundreds of microseconds.

Examples

* 1 microsecond (1 μs) – cycle time for

frequency Frequency is the number of occurrences of a repeating event per unit of time. It is also occasionally referred to as ''temporal frequency'' for clarity, and is distinct from ''angular frequency''. Frequency is measured in hertz (Hz) which is eq ...

(1 MHz), the inverse unit. This corresponds to radio wavelength

300 __NOTOC__ Year 300 ( CCC) was a leap year starting on Monday (link will display the full calendar) of the Julian calendar. At the time, it was known as the Year of the Consulship of Constantius and Valerius (or, less frequently, year 1053 ''Ab ...

m (AM medium wave band), as can be calculated by multiplying 1 μs by the

speed of light The speed of light in vacuum, commonly denoted , is a universal physical constant that is important in many areas of physics. The speed of light is exactly equal to ). According to the special theory of relativity, is the upper limit ...

(approximately ). * 1 microsecond – the length of time of a high-speed, commercial

strobe light A strobe light or stroboscopic lamp, commonly called a strobe, is a device used to produce regular flashes of light. It is one of a number of devices that can be used as a stroboscope. The word originated from the Ancient Greek ('), meaning ...

flash (see

air-gap flash An air-gap flash is a photographic light source capable of producing sub-microsecond light flashes, allowing for (ultra) high-speed photography. This is achieved by a high-voltage (20 kV typically) electric discharge between two electrodes o ...

). * 1 microsecond –

protein folding Protein folding is the physical process by which a protein chain is translated to its native three-dimensional structure, typically a "folded" conformation by which the protein becomes biologically functional. Via an expeditious and reproduc ...

takes place on the order of microseconds. * 1.8 microseconds – the amount of time subtracted from the Earth's day as a result of the

2011 Japanese earthquake Eleven or 11 may refer to: *11 (number), the natural number following 10 and preceding 12 * one of the years 11 BC, AD 11, 1911, 2011, or any year ending in 11 Literature * ''Eleven'' (novel), a 2006 novel by British author David Llewellyn *'' ...

. * 2 microseconds – the lifetime of a

muonium Muonium is an exotic atom made up of an antimuon and an electron, which was discovered in 1960 by Vernon W. Hughes and is given the chemical symbol Mu. During the muon's lifetime, muonium can undergo chemical reactions. Due to the mass diffe ...

particle * 2.68 microseconds – the amount of time subtracted from the Earth's day as a result of the 2004 Indian Ocean earthquake. * 3.33564095 microseconds – the time taken by

light Light or visible light is electromagnetic radiation that can be perceived by the human eye. Visible light is usually defined as having wavelengths in the range of 400–700 nanometres (nm), corresponding to frequencies of 750–420 te ...

to travel one kilometre in a

vacuum A vacuum is a space devoid of matter. The word is derived from the Latin adjective ''vacuus'' for "vacant" or " void". An approximation to such vacuum is a region with a gaseous pressure much less than atmospheric pressure. Physicists often di ...

* 5.4 microseconds – the time taken by light to travel one mile in a vacuum (or radio waves point-to-point in a near vacuum) * 8.01 microseconds – the time taken by light to travel one mile in typical single-mode fiber optic cable * 10 microseconds (μs) – cycle time for frequency 100 kHz, radio wavelength 3 km * 18 microseconds – net amount per year that the length of the day lengthens, largely due to

tidal acceleration Tidal acceleration is an effect of the tidal forces between an orbiting natural satellite (e.g. the Moon) and the primary planet that it orbits (e.g. Earth). The acceleration causes a gradual recession of a satellite in a prograde orbit away f ...

. * 20.8 microseconds – sampling interval for digital audio with 48,000 samples/s * 22.7 microseconds – sampling interval for CD audio (44,100 samples/s) * 38 microseconds – discrepancy in

GPS The Global Positioning System (GPS), originally Navstar GPS, is a satellite-based radionavigation system owned by the United States government and operated by the United States Space Force. It is one of the global navigation satellite sy ...

satellite A satellite or artificial satellite is an object intentionally placed into orbit in outer space. Except for passive satellites, most satellites have an electricity generation system for equipment on board, such as solar panels or radioi ...

time per day (compensated by clock speed) due to relativity * 50 microseconds – cycle time for highest human-audible tone (20 kHz) * 50 microseconds – to read the access latency for a modern solid state drive which holds non-volatile computer data * 100 microseconds (0.1 ms) – cycle time for frequency 10 kHz * 125 microseconds – common sampling interval for telephone audio (8000 samples/s) * 164 microseconds –

half-life Half-life (symbol ) is the time required for a quantity (of substance) to reduce to half of its initial value. The term is commonly used in nuclear physics to describe how quickly unstable atoms undergo radioactive decay or how long stable at ...

polonium Polonium is a chemical element with the symbol Po and atomic number 84. Polonium is a chalcogen. A rare and highly radioactive metal with no stable isotopes, polonium is chemically similar to selenium and tellurium, though its metallic character ...

-214 * 240 microseconds – half-life of

copernicium Copernicium is a synthetic chemical element with the symbol Cn and atomic number 112. Its known isotopes are extremely radioactive, and have only been created in a laboratory. The most stable known isotope, copernicium-285, has a half-life of ap ...

-277 * 260 to 480 microseconds - return trip ICMP ping time, including operating system kernel TCP/IP processing and answer time, between two gigabit ethernet devices connected to the same local area network switch fabric. * 277.8 microseconds – a fourth (a 60th of a 60th of a second), used in astronomical calculations by

al-Biruni Abu Rayhan Muhammad ibn Ahmad al-Biruni (973 – after 1050) commonly known as al-Biruni, was a Khwarazmian Iranian in scholar and polymath during the Islamic Golden Age. He has been called variously the "founder of Indology", "Father of Co ...

and Roger Bacon in 1000 and 1267 AD, respectively. * 489.67 microseconds – time for light at a 1550 nm frequency to travel 100 km in a singlemode fiber optic cable (where speed of light is approximately 200 million metres per second due to its index of refraction). * The average human eye blink takes 350,000 microseconds (just over second). * The average human finger snap takes 150,000 microseconds (just over second). * A

camera flash A flash is a device used in photography that produces a brief burst of light (typically lasting 1/1000 to 1/200 of a second) at a color temperature of about 5500 K to help illuminate a scene. A major purpose of a flash is to illuminate a ...

illuminates for 1,000 microseconds. * Standard camera shutter speed opens the shutter for 4,000 microseconds or 4 milliseconds. * 584542 years of microseconds fit in 64 bits: (2**64)/(1e6*60*60*24*365.25)

References

External links

The National Institute of Standards and Technology (NIST)
{{DEFAULTSORT:1 E-6 S Orders of magnitude (time) de:Sekunde#Abgeleitete Maßeinheiten

Examples

See also

References

External links