Measurement

From ArticleWorld

Measurement is the process of comparing a quantitative property with a unit of the same type of property. The concept of measurement is applied in several fields of knowledge. These include not just science and technology, but also domains of commerce; where measurement plays an important role in campaigns like market research and consumer response surveys.

Measuring instruments

The measuring instrument used depends upon the physical quantity to be studied. Instruments commonly used include thermometers for measuring temperature, speedometers for estimating the speed of moving vehicles, weighing scales for measuring the weight of objects and electrical measuring instruments like ammeters and voltmeters. Apart from the most obvious forms of instruments, there can be huge, complicated systems of instruments integrating several functionalities. Examples include panels in steel and textile automation and aircraft controls. Before measurements are carried out, instruments have to be properly calibrated to desired levels of accuracy.

Units and systems of measurement

The specification of units is of primary importance to measurement. Units may be fundamental, as those of length, time and mass, or derived, such as those of area, volume, acceleration and power. A more comprehensive set of fundamental units was decided upon by the General Conference of Weights and Measures in 1960 when six units were chosen, thus giving birth to the Systems International (SI) as a standard of units. Many national standards have been maintained since then in a number of countries in the world. To maintain consistency in the use of units, other systems like the foot-pound-second (fps) and the centimetre-gram-second (cgs) have also been in use.