# 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)

condensation number
In physics, the ratio of the number of molecules condensing on a surface to the total number of molecules touching that surface.
constant
A quality of a measurement that never changes in magnitude; for example, gravitational forces on earth or another planet is constant and does not change.
conversion
The change from one measurement system to another by use of a common value; such as, the conversion of feet to meters.
cord
A unit for measuring the volume of wood cut for fuel.

One cord equals 128 cubic feet (3.456 cubic meters), or a stack eight feet (2.4 meters) long, four feet (1.2 meters) wide, and four feet high.

coulomb, C
An SI unit of electrical charge.

One coulomb is the quantity of electricity conveyed by a current of one ampere in one second.

cube
A solid that has six square sides, with each at right angles to each adjacent side.
cubic centimeter, cc
1. A metric unit of volume equal to one thousandth of a liter.
2. A unit of capacity, being that of a cube each side of which measures one centimeter; equal to one milliliter.
cubit
The earliest known unit of length, which originated between 2800 and 2300 B.C.

It is approximately 50.5 centimeters/20.6 inches long, which is about the length of the human forearm measured from the tip of the middle finger to the elbow.

curie, Ci
1. The basic unit of radioactivity.

Named after Marie Curie, it is equal to the radioactivity emitted by a gram of radium, or 37 billion disintegrations per second. The Three Mile Island nuclear accident released about 50 curies.

2. A former unit of radioactivity, equal to 3.7 x 1010 becquerels (radioactive disintegrations).

curve
A line that is continuously bent, as in the arc of a circle.
cylinder, mathematical
A solid that has two equal-sided circular bases and a third side that joins the bases.
decagon
A polygon (multiple angles) having ten sides.
decimal system
The system of notation for real numbers that uses place values and base 10.

The numbers to the right of the decimal point represent a fractional part of a whole number.

degree
A unit of angular measurement; for example, a circle is divided into 360 degrees.

Degrees are indicated by the ° symbol, so 50° means 50 degrees.

degree, °C
Symbol for degrees Celsius; sometimes, called centigrade.

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