# 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)

In general, it has three inside angles, which add up to 180 degrees. Triangles are divided into three basic types: obtuse, right, and acute; triangles named by the characteristics of their sides are equilateral (all sides or faces equal), isosceles (two sides of equal length), and scalene (three sides of different lengths).

If a quantity has magnitude, but not direction, it is called a scalar. Temperature, length, and mass are examples of scalars.

For motion in one dimension, such as along the number line, velocity is a scalar and for motion in two dimensions or through three-dimensional space, velocity is a vector.

It is often expressed as *cubic*, as in cubic inches or cubic centimeters.

The science of measurement standards and methods is known as metrology.

### Today the chief systems are the English units of measurement and the metric system

The United States is one of the few countries still using the English system; all other major nations have either converted to the metric system or committed themselves to conversion.

The English system is much older and is said to be less practical than the metric system, and in the United States there has been considerable discussion in favor of adopting the metric system as the principal system; however, attempts to legislate such a change in the U.S. Congress have failed.

The basic units of the English system, the yard of length and the pound of mass, are now defined in terms of the metric standards, the meter of length and the kilogram of mass.

A whole number is an integer which has one or more units and can be positive or negative.

Zero is neither negative nor positive.

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