A nanosecond (ns) 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 billionth of a second, that is, of a second, or 10 seconds. The term combines the SI prefix ''

nano- Nano (symbol n) is a unit prefix meaning "one billionth". Used primarily with the metric system, this prefix denotes a factor of 10−9 or . It is frequently encountered in science and electronics for prefixing units of time and length. ;Exam ...

'' indicating a 1 billionth submultiple of an SI unit (e.g. nanogram, nanometre, etc.) and ''second'', the primary unit of time in the SI. A nanosecond is equal to 1000 picoseconds or

microsecond A microsecond is a unit of time 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 is not available. A microsecond is equal to 1000 ...

. Time units ranging between 10 and 10 seconds are typically expressed as tens or hundreds of nanoseconds. Time units of this granularity are commonly found in

telecommunications Telecommunication is the transmission of information by various types of technologies over wire, radio, optical, or other electromagnetic systems. It has its origin in the desire of humans for communication over a distance greater than that fe ...

, pulsed

laser A laser is a device that emits light through a process of optical amplification based on the stimulated emission of electromagnetic radiation. The word "laser" is an acronym for "light amplification by stimulated emission of radiation". The fi ...

s, and related aspects of

electronics The field of electronics is a branch of physics and electrical engineering that deals with the emission, behaviour and effects of electrons using electronic devices. Electronics uses active devices to control electron flow by amplification ...

Common measurements

* 0.001 nanoseconds – one picosecond * 0.5 nanoseconds – the

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 beryllium-13. * 0.96 nanoseconds –

100 Gigabit Ethernet 40 Gigabit Ethernet (40GbE) and 100 Gigabit Ethernet (100GbE) are groups of computer networking technologies for transmitting Ethernet frames at rates of 40 and 100 gigabits per second (Gbit/s), respectively. These technologies offer significantly ...

Interpacket gap In computer networking, the interpacket gap (IPG), also known as interframe spacing, or interframe gap (IFG), is a pause which may be required between network packets or network frames. Depending on the physical layer protocol or encoding used, ...

* 1.0 nanosecond – cycle time of an electromagnetic wave with a

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 ...

of 1 GHz (1

hertz The hertz (symbol: Hz) is the unit of frequency in the International System of Units (SI), equivalent to one event (or cycle) per second. The hertz is an SI derived unit whose expression in terms of SI base units is s−1, meaning that o ...

). * 1.0 nanosecond – electromagnetic

wavelength In physics, the wavelength is the spatial period of a periodic wave—the distance over which the wave's shape repeats. It is the distance between consecutive corresponding points of the same phase on the wave, such as two adjacent crests, t ...

of 1

light-nanosecond An unusual unit of measurement is a unit of measurement that does not form part of a coherent system of measurement, especially because its exact quantity may not be well known or because it may be an inconvenient multiple or fraction of a bas ...

. Equivalent to 0.3m radio band. * nanoseconds (by definition) – time taken by light to travel 1 foot in a vacuum.By definition of the "foot" as exactly 1/3 yards, and of the

international yard The international yard and pound are two units of measurement that were the subject of an agreement among representatives of six nations signed on 1 July 1959: the United States, United Kingdom, Canada, Australia, New Zealand, and South Africa. T ...

as "exactly 0.9144 metres", and of the metre (SI unit) defined by the

International Bureau of Weights and Measures The International Bureau of Weights and Measures (french: Bureau international des poids et mesures, BIPM) is an intergovernmental organisation, through which its 59 member-states act together on measurement standards in four areas: chemistry ...

as the "length of the path traveled by light in vacuum during a time interval of 1/299792458 of a second". The time taken by light to travel 1 foot in a vacuum is therefore (1/299792458)x(0.9144/3) seconds, or nanoseconds. * nanoseconds (by definition) – 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 1

metre The metre (British spelling) or meter (American spelling; see spelling differences) (from the French unit , from the Greek noun , "measure"), symbol m, is the primary unit of length in the International System of Units (SI), though its prefi ...

in a vacuum. * 8 nanoseconds - typical

propagation delay Propagation delay is the time duration taken for a signal to reach its destination. It can relate to networking, electronics or physics. ''Hold time'' is the minimum interval required for the logic level to remain on the input after triggering ed ...

of 74HC series logic chips based on

HCMOS HCMOS ("high-speed CMOS") is the set of specifications for electrical ratings and characteristics, forming the 74HC00 family, a part of the 7400 series of integrated circuits.

technology, commonly used for digital electronics in the mid-1980s. * 10 nanoseconds – one " shake", (as in a "shake of a lamb's tail") approximate time of one generation of a nuclear chain reaction with fast neutrons * 10 nanoseconds – cycle time for frequency 100 MHz (1

), radio wavelength 3 m ( VHF,

FM band The FM broadcast band is a range of radio frequencies used for FM broadcasting by radio stations. The range of frequencies used differs between different parts of the world. In Europe and Africa (defined as International Telecommunication Union ( ...

) * 10 nanoseconds – half-life of lithium-12 * 12 nanoseconds – mean lifetime of a charged K meson * 20–40 nanoseconds – time of fusion reaction in a hydrogen bomb * 30 nanoseconds – half-life of

carbon-21 Carbon (6C) has 15 known isotopes, from to , of which and are stable. The longest-lived radioisotope is , with a half-life of years. This is also the only carbon radioisotope found in nature—trace quantities are formed cosmogenically by ...

* 77 nanoseconds – a sixth (a 60th of a 60th of a 60th of a 60th of a second) * 96 nanoseconds –

Gigabit Ethernet In computer networking, Gigabit Ethernet (GbE or 1 GigE) is the term applied to transmitting Ethernet frames at a rate of a gigabit per second. The most popular variant, 1000BASE-T, is defined by the IEEE 802.3ab standard. It came into use ...

* 100 nanoseconds – cycle time for

10 MHz, radio wavelength 30 m ( shortwave) * 299 nanoseconds – half-life of polonium-212 * 333 nanoseconds – cycle time of highest medium wave radio frequency, 3 MHz * 500 nanoseconds – T1 time of Josephson

phase qubit In quantum computing, and more specifically in superconducting quantum computing, the phase qubit is a superconducting device based on the superconductor–insulator–superconductor (SIS) Josephson junction, designed to operate as a quantum bit, ...

(see also

Qubit In quantum computing, a qubit () or quantum bit is a basic unit of quantum information—the quantum version of the classic binary bit physically realized with a two-state device. A qubit is a two-state (or two-level) quantum-mechanical system, ...

) as of May 2005 * 1,000 nanoseconds – one

References

;Notes ;Citations

External links

Visual representation of a nanosecond

Grace Hopper Grace Brewster Hopper (; December 9, 1906 – January 1, 1992) was an American computer scientist, mathematician, and United States Navy rear admiral. One of the first programmers of the Harvard Mark I computer, she was a pioneer of compu ...

explains the nanosecond {{DEFAULTSORT:1 E-9 S Orders of magnitude (time)

Common measurements

See also

References

External links