International Standard ISO 31 (Quantities and units, International Organization for Standardization, 1992) is the most widely respected style guide for the use of units of measurement, and formulas involving them, in scientific and educational documents worldwide. In most countries, the notations used in mathematics and science textbooks at schools and universities follow exactly the guidelines given by ISO 31. A physical quantity is either a quantity within physics that can be measured (e. ... In physics and metrology, units are standards for measurement of physical quantities that need clear definitions to be useful. ... Logo of the International Organization for Standardization The International Organization for Standardization (ISO or iso) is an international standard-setting body made up of representatives from national standards bodies. ... In classical physics and engineering, measurement is the the result of comparing physical quantities of objects, relations (e. ...

The standard comes in 14 parts:

ISO 31-0: General principles

ISO 31-1: Space and time

ISO 31-2: Periodic and related phenomena

ISO 31-3: Mechanics

ISO 31-4: Heat

ISO 31-5: Electricity and magnetism

ISO 31-6: Light and related electromagnetic radiations

ISO 31-7: Acoustics

ISO 31-8: Physical chemistry and molecular physics

ISO 31-9: Atomic and nuclear physics

ISO 31-10: Nuclear reactions and ionizing radiations

ISO 31-11: Mathematical signs and symbols for use in the physical sciences and technology

ISO 31-12: Characteristic numbers

ISO 31-13: Solid state physics

ISO 31-0 is the introductory part of international standard ISO 31 on quantities and units. ... ISO 31-1 is the part of the international standard on quantities and units (ISO 31) that defines names and symbols for quantities and units related to space and time. ... Space has a range of definitions. ... 8:17 am, August 6, 1945, Japanese time. ... A phenomenon (plural: phenomena) is an observable event, especially something special (literally something that can be seen from the Greek word phainomenon = observable). ... A red-hot iron rod cooling after being worked by a blacksmith. ... Electricity is a property of certain subatomic particles (e. ... In physics, magnetism is a phenomenon by which materials exert an attractive or repulsive force on other materials. ... Prism splitting light Light is electromagnetic radiation with a wavelength that is visible to the eye, or in a more general sense, any electromagnetic radiation in the range from infrared to ultraviolet. ... Electromagnetic radiation or EM radiation is a combination (cross product) of oscillating electric and magnetic fields perpendicular to each other, moving through space as a wave, effectively transporting energy and momentum. ... Look up Acoustic in Wiktionary, the free dictionary For the study of sound, a branch of physics, see acoustics. ... Chemistry (in Greek: χημεία) is the science of matter and its interactions with energy and itself (see physics, biology). ... Molecular physics is the study of the physical properties of molecules and of the chemical bonds between atoms that bind them into molecules. ... Nuclear physics is the branch of physics concerned with the nucleus of the atom. ... In nuclear physics, a nuclear reaction is a process in which two nuclei or nuclear particles collide, to produce products different to the initial products. ... Ionizing radiation is radiation in which an individual particle (for example, a photon, electron, or helium nucleus) carries enough energy to ionize an atom or molecule (that is, to completely remove an electron from its orbit). ... Technology (Gr. ... A number is an abstract entity used originally to describe quantity. ... Solid-state physics, the largest branch of condensed matter physics, is the study of rigid matter, or solids. ...

See also

• SI – the international system of units
• BIPM – publishes freely available information on SI units, which overlaps with some of the material covered in ISO 31-0
• IUPAP – much of the material in ISO 31 comes originally from the Commission for Symbols, Units and Nomenclature (SUN Commission) of the International Union of Pure and Applied Physics
• IUPAC – some of the material in ISO 31 originates from the Interdivisional Committee on Nomenclature and Symbols of the International Union of Pure and Applied Chemistry

The International System of Units (abbreviated SI from the French phrase, Système International dUnités) is the most widely used system of units. ... The Bureau International des Poids et Mesures (International Bureau of Weights and Measures, or BIPM) is a standards organization, one of the three organizations established to maintain the SI system under the terms of the Metre Convention. ... ISO 31-0 is the introductory part of international standard ISO 31 on quantities and units. ... The International Union of Pure and Applied Physics (IUPAP) is an international non-governmental organization devoted to the advancement of Physics. ... The International Union of Pure and Applied Chemistry (IUPAC) is an international non-governmental organization devoted to the advancement of chemistry. ...

References

ISO standards are available for purchase online. All parts of ISO 31 along with ISO 1000 are available in book form as

ISO Standards Handbook: Quantities and units. 3rd ed., International Organization for Standardization, Geneva, 1993, 345 p., ISBN 92-67-10185-4, 182.00 CHF. http://www.iso.ch/iso/en/prods-services/otherpubs/Handbooks.PublicationList?CLASSIFICATION=HANDBOOKS