Search results
Results from the WOW.Com Content Network
A decametre (International spelling as used by the International Bureau of Weights and Measures and by most English speaking countries, [1] [2] United States spelling dekameter or decameter [3] [4]), symbol dam ("da" for the SI prefix deca-, [1] "m" for the SI unit metre), is a unit of length in the International System of Units (SI) equal to ten metres.
22 cm = 2.2 dm – diameter of a typical association football (soccer ball) 30 cm = 3 dm – typical school-use ruler length (= 300 mm) 30.48 cm = 3.048 dm – 1 foot (measure) 60 cm = 6 dm – standard depth (front to back) of a domestic kitchen worktop in Europe (= 600 mm) 90 cm = 9 dm – average length of a rapier, a fencing sword [30]
The prefix was a part of the original metric system in 1795. It is not in very common usage, although the decapascal is occasionally used by audiologists.The decanewton is also encountered occasionally, probably because it is an SI approximation of the kilogram-force.
Meaning SI unit of measure alpha: alpha particle: angular acceleration: radian per second squared (rad/s 2) fine-structure constant: unitless beta: velocity in terms of the speed of light c: unitless beta particle: gamma: Lorentz factor: unitless photon: gamma ray: shear strain: radian
The femtometre, used mainly in particle physics, is sometimes called a fermi. For large scales, megametre, gigametre, and larger are rarely used. Instead, ad hoc non-metric units are used, such as the solar radius, astronomical units, light years, and parsecs; the astronomical unit is mentioned in the SI standards as an accepted non-SI unit.
Measure for how easily current flows through a material siemens (S = Ω −1) L −2 M −1 T 3 I 2: scalar Electrical conductivity: σ: Measure of a material's ability to conduct an electric current S/m L −3 M −1 T 3 I 2: scalar Electric potential: φ: Energy required to move a unit charge through an electric field from a reference point ...
The constants listed here are known values of physical constants expressed in SI units; that is, physical quantities that are generally believed to be universal in nature and thus are independent of the unit system in which they are measured.
In atomic physics, sub-atomic physics, and cosmology, the preferred unit of length is often related to a chosen fundamental physical constant, or combination thereof. This is often a characteristic radius or wavelength of a particle. Some common natural units of length are included in this table: