Measurements and Mathematics Terms

(mathematics is the deductive study of quantities, magnitudes, and shapes as determined by the use of numbers and symbols while every branch of science and engineering depends on mathematics; measurement is the process of associating numbers with physical quantities and phenomena and measurement is fundamental to the sciences; to engineering, construction, and other technical fields; and to almost all everyday activities)

1. Scientific method, observation and facts
The observation of phenomena and the recording of facts: the phenomena are what occurs in the environment; the facts are descriptions of what is observed.
2. Scientific method, formlation of physical laws and generalizations
The formulation of physical laws from the generalization of the phenomena: physical laws are the way nature usually behaves based on what has been observed in the past.
3. Scientific method, developoment of theory to predict new phenomena
The development of a theory that is used to predict new phenomena where the theory is a general statement that explains the facts.

A theory can lead to a new conclusion or the discovery of a phenomenon. Developments of a theory often result in a change in paradigm; that is, looking at or thinking about a scientific problem in a totally different way as indicated by a set of assumptions, concepts, values, and practices that constitute a way of viewing reality for the scientific community that shares them.

—Based on information compiled from "Why Is Measurement Important to Science?"
by Patricia Barnes-Svarney, Editorial Director; The New York Public Library Science Desk Reference;
A Stoneson Press Book, Macmillan Publishers; New York; 1995; page 2.
abampere
An electric current equal to 10 amperes; one ampere represents a current flow of one coulomb of charge per second.
abcoulomb
Electric charge equal to ten coulombs (the amount of charge accumulated in one second by a current of one ampere).
abscissa
The horizontal coordinate on a plane which is measured from the y (vertical) axis.
absolute weight
The weight (or mass) of a body in a vacuum or the weight of a body considered apart from all modifying influences; such as, the atmosphere.

To determine its absolute weight, a body must be weighed in a vacuum or an allowance must be made for buoyancy (tendency or capacity to remain afloat in a liquid or to rise in air or gas).

abstract number
A number with no associated units.
acceleration
1. The rate of change of a moving body's velocity which has two components: speed and direction; so, a body's acceleration is altered by either a change in speed, a change in direction, or both.
2. The acceleration due to gravity, for instance, is 32 feet (9.8 meters) per second per second; means that for every second an object falls, its velocity is increasing, too.
accelerometer apparatus
A device which is either mechanical or electromechanical, for measuring acceleration or deceleration; that is, the rate of increase or of decrease in the velocity of a moving object.
accuracy
How close a measurement comes to the actual, or true, value.

The true value is the value currently accepted by a certain field of science.

acre-foot
1. The volume of water that would cover an area of one acre to a depth of one foot, equal to 1,233.5 cubic meters (43,560 cubic feet).
2. A unit that is sometimes used to measure large volumes of water; such as, the capacity of a reservoir (equal to its area in acres multiplied by its average depth in feet).
acute angle
An angle that has a measure of less than 90°.
altitude
1. The measurement of height, usually given in meters above sea level.
2. The angular distance; usually measured in degrees, above the horizon, from zero degrees at the horizon to 90 degrees at the zenith.

One of the two co-ordinates (the other being azimuth) that define a celestial object's position, used with an altazimuth mount.

ampere hour meter
An instrument that monitors current with time.

The indication is the product of current (in amperes) and time (in hours).

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