Intensity may refer to:

In colloquial use

Amplitude The amplitude of a periodic variable is a measure of its change in a single period (such as time or spatial period). The amplitude of a non-periodic signal is its magnitude compared with a reference value. There are various definitions of amplit ...

* Level (disambiguation) *

Magnitude (disambiguation) Magnitude may refer to: Mathematics *Euclidean vector, a quantity defined by both its magnitude and its direction *Magnitude (mathematics), the relative size of an object *Norm (mathematics), a term for the size or length of a vector *Order of ...

In physical sciences

Physics

* Intensity (physics), power per unit area (W/m²) *

Field strength In physics, field strength means the ''magnitude'' of a vector-valued field (e.g., in volts per meter, V/m, for an electric field ''E''). For example, an electromagnetic field results in both electric field strength and magnetic field strength. As ...

of electric, magnetic, or electromagnetic fields (V/m, T, etc.) *

Intensity (heat transfer) In the field of heat transfer, intensity of radiation I is a measure of the distribution of radiant heat flux per unit area and solid angle, in a particular direction, defined according to :dq = I\, d\omega\, \cos \theta\, dA where *dA is the in ...

, radiant heat flux per unit area per unit solid angle (W·m⁻²·sr⁻¹) *

Electric current An electric current is a stream of charged particles, such as electrons or ions, moving through an electrical conductor or space. It is measured as the net rate of flow of electric charge through a surface or into a control volume. The moving pa ...

, whose value is sometimes called ''current intensity'' in older books

Optics

Radiant intensity In radiometry, radiant intensity is the radiant flux emitted, reflected, transmitted or received, per unit solid angle, and spectral intensity is the radiant intensity per unit frequency or wavelength, depending on whether the spectrum is taken ...

, power per unit solid angle (W/sr) * Luminous intensity, luminous flux per unit solid angle (lm/sr or cd) *

Irradiance In radiometry, irradiance is the radiant flux ''received'' by a ''surface'' per unit area. The SI unit of irradiance is the watt per square metre (W⋅m−2). The CGS unit erg per square centimetre per second (erg⋅cm−2⋅s−1) is often used ...

, power per unit area (W/m²)

Astronomy

* Radiance, power per unit solid angle per unit projected source area (W·sr⁻¹·m⁻²)

Seismology

Mercalli intensity scale The Modified Mercalli intensity scale (MM, MMI, or MCS), developed from Giuseppe Mercalli's Mercalli intensity scale of 1902, is a seismic intensity scale used for measuring the intensity of shaking produced by an earthquake. It measures the eff ...

, a measure of earthquake impact * Japan Meteorological Agency seismic intensity scale, a measure of earthquake impact * Peak ground acceleration, a measure of earthquake acceleration (g or m/s²)

Acoustics

Sound intensity Sound intensity, also known as acoustic intensity, is defined as the power carried by sound waves per unit area in a direction perpendicular to that area. The SI unit of intensity, which includes sound intensity, is the watt per square meter (W/m2 ...

, sound power per unit area

Other uses

* Value intensity in philosophy and ethics *In video

luminous emittance In photometry, illuminance is the total luminous flux incident on a surface, per unit area. It is a measure of how much the incident light illuminates the surface, wavelength-weighted by the luminosity function to correlate with human brightness ...

, the luminous flux per unit area (lm/m² or lux) *

Energy intensity Energy intensity is a measure of the energy inefficiency of an economy. It is calculated as units of energy per unit of GDP. * High energy intensities indicate a high price or cost of converting energy into GDP. * Low energy intensity indicate ...

, an economic measure of energy consumed per unit of GDP (J/$, etc.) * Carbon intensity, any of several measures of release of carbon into the environment *

Floor area ratio Floor area ratio (FAR) is the ratio of a building's total floor area (gross floor area) to the size of the piece of land upon which it is built. It is often used as one of the regulations in city planning along with the building-to-land ratio. The ...

, the ratio of the total floor area of buildings on a certain location to the size of the land of that location, or the zoning limit imposed on such a ratio *

Intensity (measure theory) In the mathematical discipline of measure theory, the intensity of a measure is the average value the measure assigns to an interval of length one. Definition Let \mu be a measure on the real numbers. Then the intensity \overline \mu of ...

, the average value a measure assigns to an interval of length one * Exercise intensity, a measure of how much work is done during exercise (% of max heart rate) * ''Intensity'' (novel), a 1995 novel by Dean Koontz ** ''Intensity'' (film), a 1997 made-for-TV movie based on the novel * ''Intensity'' (Charles Earland album), 1972 * ''Intensity'' (Art Pepper album), 1960 * ''Intensity'' (John Klemmer album), 1973 *''

Intensity! ''Intensity!'' is the second studio album released by Croatian surf rock band The Bambi Molesters. The album was recorded in December 1998 and was released in 1999. Background In 1999, the band signed to Dancing Bear Records. The release of the ...

'', a 1999 album by The Bambi Molesters * ''Intensity'' (video game), a 1988 video game. *"Intensity", a song by Linda Perhacs from the album '' The Soul of All Natural Things''