Measurements and Mathematics Terms

Any of the assumptions on which a mathematical theory is based.

An instrument for measuring the mass of an object.

With a conventional balance, the object is placed in a pan while a known weight is placed in a pan opposite a fulcrum. If the pans are level, the materials in the two pans are of equal weight.

A visual representation of horizontal and vertical bars or lines to represent data.

A unit of liquid capacity, the value of which depends on the liquid being measured.

It is used for petroleum, a barrel of which contains 159 liters (58 U.S. gallons); a barrel of alcohol contains 189 liters (69 U.S. gallons).

A numbering system in which each place to the left or right of the decimal represents a power of 10.

In engineering, a unit of electrical signaling speed equal to one pulse per second, measuring the rate at which signals are sent between electronic devices; such as, telegraphs and computers.

For example, 300 baud (or bauds) is about 300 words a minute or a unit of speed in data transmission of a computer equal to one bit per second; or, a unit of transmission speed for electronic signals, corresponding to one information unit or event per second.

Named after Jean Maurice Emile Baudot (1845-1903), a French engineer.

An SI (Système International d'Unités) International System of Units of radioactivity, equal to one radioactive disintegration (change in he nucleus of an atom when a particle or ray is given off) per second or equal to the activity resulting from the decay of one nucleus of radioactive matter in one second or other nuclear transformation per second.

Named after the French physicist, Antoine Henri Becquerel, who discovered that rays emitted by uranium salts affect photographic plates (1852-1908).

A unit of sound measurement equal to ten decibels.

It is named for the Scottish-born U.S. scientist Alexander Graham Bell (1847-1922).

The shape of a graph that indicates normal distribution.

A nautical term applied to half-hours by "watch".

A day is divided into seven watches, five of four hours each and two, called "dogwatches", of two hours.

Each half-hour of each watch is indicated by the striking of a bell, eight bells signaling the end of the watch.

A sensitive thermometer that measures the energy of radiation by registering the change in electrical resistance of a fine wire when it is exposed to heat or light.

It was devised in 1880 by the U.S astronomer Samuel Langley (1834-1906) for measuring radiation from the stars.

A unit for measuring the reaction of optical materials to stress, defined in terms of the slowing down of light passing through the material when it is stretched or compressed.

A United Kingdom (British) national standards body.

Although government funded, the institution is independent. The BSI interprets international technical standard for the U.K., and it also sets its own standards.

An imperial unit of heat, now replaced in the SI system by the joule (one British thermal unit is approximately 1,055 joules).

Burning one cubic foot of natural gas releases about 1,000 Btu of heat.

A dry or liquid measure equal to eight gallons or four pecks (2,219.36 cubic inches/36.37 liters) in the U.K.; some U.S. states have different standards depending on the goods being measured.