SI derived unit

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SI derived unit

SI derived units are part of the SI

Si, si, or SI may refer to :...
system of measurement unit

Units of measurement

The definition, agreement and practical use of units of measurement have played a crucial role in human endeavour from early ages up to this day....
s and are derived from the seven SI base unit

SI base unit

The International System of Units defines seven dimensional analysis SI base units. All other physical units can be derived from these base units: these are known as SI derived units....
s.

Note that while the names of all SI units are in lowercase, the symbols of units named after people are written with an initial capital letter (eg: meter, m; hertz, Hz). The exception is degrees Celsius, which refers to degrees on the Celsius

Celsius

Celsius is a temperature scale that is named after the Swedish astronomer Anders Celsius , who developed a similar temperature scale two years before his death....
scale.
units can be put together to derive units of measurement for other quantities.

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Encyclopedia

SI derived units are part of the SI

Si, si, or SI may refer to :...
system of measurement unit

Units of measurement

The definition, agreement and practical use of units of measurement have played a crucial role in human endeavour from early ages up to this day....
s and are derived from the seven SI base unit

SI base unit

Celsius

Celsius is a temperature scale that is named after the Swedish astronomer Anders Celsius , who developed a similar temperature scale two years before his death....
scale.

Derived units with special names

Base units can be put together to derive units of measurement for other quantities. In addition to the two dimensionless

Dimensionless quantity

In dimensional analysis, a dimensionless quantity is a quantity without any physical units and thus a pure number. Such a number is typically defined as a product or ratio of quantity which do have units, in such a way that all the units cancel out....
derived units radian
Radian

The radian is a unit of plane angle, equal to 180/pi Degree , or about 57.2958 degrees, or about 57?17'45?. It is the standard unit of angular measurement in all areas of mathematics beyond the elementary level....
(rad) and steradian
Steradian

The steradian is the SI unit of solid angle. It is used to describe two-dimensional angular spans in three-dimensional space, analogous to the way in which the radian describes angles in a Plane ....
(sr) there are 20 derived units having special names:

style="font-size:larger;font-weight:bold;"|Named units derived from SI
Si

Si, si, or SI may refer to :...
base units
Name	Symbol Symbol A symbol is something such as an entity, picture, written word, sound, or particular mark that represents something else by association, resemblance, or convention....	Quantity Physical quantity A physical quantity is a physical property that can be Quantitative. This means it can be measured and/or calculated and expressed in numbers. For example, "weight" is a physical quantity that can be expressed by stating a number of some basic measurement unit such as pound or kilograms, while "beauty" is a property that is difficult to desc...	Expression in terms of other units	Expression in terms of SI base unit SI base unit The International System of Units defines seven dimensional analysis SI base units. All other physical units can be derived from these base units: these are known as SI derived units.... s
hertz Hertz The hertz is a measure of frequency per unit of time, or the number of list of cycles per second. It is the SI base unit of frequency in the International System of Units , and is used worldwide in both general-purpose and scientific contexts....	Hz	frequency Frequency Frequency is the number of occurrences of a repeating event per unit time. It is also referred to as temporal frequency.The period is the duration of one cycle in a repeating event, so the period is the reciprocal of the frequency....	1/s	s^-1
radian Radian The radian is a unit of plane angle, equal to 180/pi Degree , or about 57.2958 degrees, or about 57?17'45?. It is the standard unit of angular measurement in all areas of mathematics beyond the elementary level....	rad	angle Angle In geometry and trigonometry, an angle is the figure formed by two Ray sharing a common endpoint, called the vertex of the angle . The magnitude of the angle is the "amount of rotation" that separates the two rays, and can be measured by considering the length of circular arc swept out when one ray is rotated about the vertex to coincide...	m m^-1	dimensionless
steradian Steradian The steradian is the SI unit of solid angle. It is used to describe two-dimensional angular spans in three-dimensional space, analogous to the way in which the radian describes angles in a Plane ....	sr	solid angle Solid angle The solid angle, O, is the angle in three-dimensional space that an object subtends at a point. It is a measure of how big that object appears to an observer looking from that point....	m² m^-2	dimensionless
newton Newton The newton is the International System of Units SI derived unit of force, named after Isaac Newton in recognition of his work on classical mechanics....	N	force Force In physics, a force is that which can cause an object with mass to change its velocity. Force has both Euclidean_vector#Length of a vector and Direction , making it a Vector quantity.... , weight Weight In the physical sciences, weight is a measurement of the gravitational force acting on an object. Near the surface of the Earth, the Earth's gravity is approximately constant; this means that an object's weight is roughly proportional to its mass....	m·kg/s²	m·kg·s^-2
pascal Pascal (unit) The pascal is the SI derived unit of pressure, stress , Young's modulus and tensile strength. It is a measure of force per unit area i.e. equivalent to one newton per square meter or one joule per cubic meter....	Pa	pressure Pressure Pressure is the force per unit area applied to an object in a direction surface normal to the surface. Gauge pressure is the pressure relative to the local atmospheric or ambient pressure.... , stress Stress (physics) In continuum mechanics, stress is a measure of the average amount of force exerted per unit area. It is a measure of the intensity of the total internal forces acting within a body across imaginary internal surfaces, as a reaction to external applied forces and body forces....	N/m²	m^-1·kg·s^-2
joule Joule The joule is the SI derived unit of energy in the International System of Units. It is defined as:One joule is the amount of energy required to perform the following actions:...	J	energy Energy In physics, energy is a scalar physical quantity that describes the amount of Work_ that can be performed by a force. Energy is an attribute of objects and systems that is subject to a conservation law.... , work Mechanical work In physics, mechanical work is the amount of energy transferred by a force acting through a distance. Like energy, it is a scalar quantity, with SI of joules.... , heat Heat In physics and thermodynamics, heat is any transfer of energy from one body or thermodynamic system to another due to a difference in temperature....	N·m = C·V = W·s	m²·kg·s^-2
watt WATT WATT is a radio station broadcasting a News radio-Talk radio-Sports radio format. Licensed to Cadillac, Michigan, it first began broadcasting in 1945....	W	power Power (physics) In physics, power is the rate at which mechanical work is performed or energy is transmitted, or the amount of energy required or expended for a given unit of time.... , radiant flux Radiant flux In radiometry, radiant flux or radiant power is the measure of the total Power of electromagnetic radiation . The power may be the total emitted from a source, or the total landing on a particular surface....	J/s = V·A	m²·kg·s^-3
coulomb Coulomb The coulomb is the SI unit of electric charge. It is named after Charles-Augustin de Coulomb....	C	electric charge Electric charge Electric charge is a fundamental conserved property of some subatomic particles, which determines their electromagnetic interaction. Electrically charged matter is influenced by, and produces, electromagnetic fields.... or electric flux Flux In the various subfields of physics, there exist two common usages of the term flux, both with rigorous mathematical frameworks.In the study of transport phenomena , flux is defined as the amount that flows through a unit area per unit time*....	s·A	s·A
volt Volt The volt is the SI SI derived unit of electric potential difference or electromotive force, commonly known as voltage. It is named in honor of the Lombard physicist Alessandro Volta , who invented the voltaic pile, possibly the first chemical battery ....	V	voltage Voltage Electrical tension is the potential difference between two points of an electrical or electronic circuit, expressed in volts. It is the measurement of the potential for an electric field to cause an electric current in an electrical conductor.... , electrical potential difference Potential difference In physics, the potential difference or p.d. between two points is the difference of the points' scalar potential, equivalent to the line integral of the field strength between the two points.... , electromotive force Electromotive force Electromotive force is a term used to characterize electrical devices, such as voltaic cells, Thermoelectric effects, electrical generators and transformers, and even resistors....	W/A = J/C	m²·kg·s^-3·A^-1
farad Farad The farad is the SI unit of capacitance. The farad is named after the British physicist Michael Faraday....	F	electric capacitance	C/V	m⁻²·kg^-1·s⁴·A²
ohm	O	electric resistance, impedance Electrical impedance Electrical impedance, or simply impedance, describes a measure of opposition to a sinusoidal alternating current . Electrical impedance extends the concept of Electrical resistance to AC circuits, describing not only the relative amplitudes of the voltage and Electric current, but also the relative Phase .... , reactance	V/A	m²·kg·s^-3·A^-2
siemens Siemens (unit) The siemens is the SI SI derived unit of electric conductance. It is equal to inverse ohm. It is named after the Germany inventor and industrialist Ernst Werner von Siemens, and was previously called the #Mho....	S	electrical conductance Electrical conductance Electrical conductance is a measure of how easily electricity flows along a certain path through an electrical element. The SI derived unit of conductance is the Siemens ....	1/O	m^-2·kg^-1·s³·A²
weber	Wb	magnetic flux Magnetic flux Magnetic flux, represented by the Greek letter F , is a measure of quantity of magnetism, taking into account the strength and the extent of a magnetic field....	J/A	m²·kg·s^-2·A^-1
tesla Tesla (unit) The tesla is the SI derived unit of magnetic flux density B . The tesla is equal to one weber per square metre and was defined in 1960 in honor of inventor, scientist and electrical engineer Nikola Tesla....	T	magnetic field Magnetic field A magnetism field is a vector field which can exert a magnetic force on moving electric charges and on magnetic dipoles . When placed in a magnetic field, magnetic dipoles tend to align their axes parallel to the magnetic field....	V·s/m² = Wb/m² = N/(A·m)	kg·s^-2·A^-1
henry	H	inductance Inductance Inductance is the property in an electrical circuit where a change in the current flowing through that circuit induces an Electromotive force that opposes the change in current ....	V·s/A = Wb/A	m²·kg·s^-2·A^-2
degree Celsius Celsius Celsius is a temperature scale that is named after the Swedish astronomer Anders Celsius , who developed a similar temperature scale two years before his death....	°C	temperature Temperature In physics, temperature is a physical property of a Physical system that underlies the common notions of hot and cold; something that feels hotter generally has the greater temperature....	K - 273.15	K
lumen Lumen (unit) The lumen is the SI unit of luminous flux, a measure of the perceived power of light. Luminous flux differs from radiant flux, the measure of the total power of light emitted, in that luminous flux is adjusted to reflect the varying sensitivity of the human eye to different wavelengths of light....	lm	luminous flux Luminous flux In photometry , luminous flux or luminous power is the measure of the perceived power of light. It differs from radiant flux, the measure of the total power of light emitted, in that luminous flux is adjusted to reflect the varying sensitivity of the human eye to different wavelengths of light....	cd·sr	cd
lux Lux The lux is the SI unit of illuminance and luminous emittance. It is used in photometry as a measure of the apparent intensity of light hitting or passing through a surface....	lx	illuminance Illuminance In photometry , illuminance is the total luminous flux incident on a surface, per unit area. It is a measure of the intensity of the incident light, wavelength-weighted by the luminosity function to correlate with human brightness perception....	lm/m²	m^-2·cd
becquerel Becquerel The becquerel is the SI derived unit of Radioactive decay. 1 Bq is defined as the activity of a quantity of radioactive material in which one atomic nucleus decays per second....	Bq	radioactivity (decays per unit time)	1/s	s^-1
gray Gray (unit) The gray is the SI unit of absorbed dose due to ionizing radiation ....	Gy	absorbed dose Absorbed dose Absorbed dose is a measure of the energy deposited in a medium by ionizing radiation. It is equal to the energy deposited per unit mass of medium, and so has the unit J/kg, which is given the special name gray .... (of ionizing radiation Ionizing radiation Ionizing radiation consists of subatomic particle radiation or electromagnetic radiation that are energetic enough to detach electrons from atoms or molecules, ionize them.... )	J/kg	m²·s^-2
sievert Sievert The sievert is the SI derived unit of equivalent dose. It attempts to reflect the biological effects of radiation as opposed to the physical aspects, which are characterised by the absorbed dose, measured in Gray ....	Sv	equivalent dose Equivalent dose The equivalent dose is a measure of the radiation dose to tissue where an attempt has been made to allow for the different relative biological effects of different types of ionizing radiation.... (of ionizing radiation)	J/kg	m²·s^-2
katal Katal The katal is the SI unit of catalysis activity. It is a derived SI unit for expressing quantity values of catalytic activity of enzymes and other catalysts....	kat	catalytic activity	mol/s	s^-1·mol

SI derived unit

Derived units with special names

Other quantities and units

See also