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, t ...

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

is not available. A microsecond is equal to 1000 nanoseconds or of a

millisecond A millisecond (from '' milli-'' and second; symbol: ms) is a unit of time in the International System of Units (SI) equal to one thousandth (0.001 or 10−3 or 1/1000) of a second and to 1000 microseconds. A unit of 10 milliseconds may be ca ...

. Because the next

SI prefix The International System of Units, known by the international abbreviation SI in all languages and sometimes pleonastically as the SI system, is the modern form of the metric system and the world's most widely used system of measurement. ...

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 ...

(1 MHz), the inverse unit. This corresponds to radio wavelength 300 m (AM

medium wave Medium wave (MW) is the part of the medium frequency (MF) radio band used mainly for AM radio broadcasting. The spectrum provides about 120 channels with more limited sound quality than FM stations on the FM broadcast band. During the dayt ...

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 fo ...

(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). * 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 reprodu ...

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

day A day is the time period of a full rotation of the Earth with respect to the Sun. On average, this is 24 hours, 1440 minutes, or 86,400 seconds. In everyday life, the word "day" often refers to a solar day, which is the length between two so ...

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 *''El ...

. * 2 microseconds – the lifetime of a muonium 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 The mile, sometimes the international mile or statute mile to distinguish it from other miles, is a British imperial unit and United States customary unit of distance; both are based on the older English unit of length equal to 5,280 Engli ...

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. * 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

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 radioiso ...

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 ...

of polonium-214 * 240 microseconds – half-life of copernicium-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 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 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