- For an alternative meaning, see academic degree.
A degree is the name of several units of measurement, several concepts
in mathematics, and an academic qualification.
Measurement
Angle
A degree of arc, usually symbolized by the symbol °, is a measurement of plane angles, or of a location along a great circle of a sphere (such as the Earth or the celestial sphere); it represents going one-360th the way around the circumference of a circle or sphere.
The number 360 was probably chosen because it is divisible by 24 positive integers, including every number from 1 to 10 except
7. (For the number of degrees in a circle to be divisible by every number from 1 to 10, there would need to be 2520 degrees in a
circle, which is a much less convenient number).
Often, where degree measures are used, one also finds minutes (representing 1/60th of a degree and symbolized by a single
quotation mark) and seconds (1/60th of a minute, or 1/3600th of a degree, and symbolized by a double quotation mark). For
example, 40.20361° is frequently represented as 40°12'13" or 40 degrees, 12 minutes, 13 seconds. This distance is approximately
11.16% of the way around a circle.
Because the notion that there are 360 degrees in a circle is an artificial concept, more rooted in number theory than in geometry, mathematicians typically prefer to use radians, because the number of radians in an angle corresponds to the number of radii that
equal the arc length of the angle. Because there are 2π radii around a circle, 360° equals 2π radians, so 1° =
π/180 radians.
With the invention of the metric system, based on powers of ten, there was an
attempt to define a "decimal degree" (grad or gon), so that
the number of decimal degrees in a right angle would be 100, and there would be 400 decimal degrees in a circle. This idea did
not gain momentum.
Temperature
Several units of measuring temperature. The symbol is usually ° followed
by the initial letter, for example ° C.
Note that the SI unit of temperature, the kelvin,
uses the symbol K and is not preceded by "degrees" or the degree sign (°).
Degree Symbol
In Unicode, the "degree sign" is U+00B0 (°). The HTML code for it is
°.
Due to a similar appearance in some fonts in print and on computer screens, some other
characters may be mistakenly substituted for it: the "masculine ordinal indicator" (U+00BA, º), the "ring above" (U+02DA, ˚),
"superscript zero" (U+2070, ⁰), superscript zero proper (0)
or superscript letter "o" (o), and the "ring operator" (U+2218, ∘).
Mathematics and Physics
see degree (mathematics) for more information.
A degree of freedom is a concept in mathematics, physics and engineering. See the article
"degrees of freedom" for the use of this concept.
The degree of a term of a polynomial is the exponent on the variable in that term; the degree of a
polynomial is the degree of the term of highest degree.
In graph theory, the degree of a vertex of a graph is the number
of edges incident to that vertex.
In topology, degree is a number which is defined for maps between manifolds of
the same dimension.
Education
A degree is an award conferred on a person by an
institution of higher education, generally in recognition of
academic achievement, but in some cases merely as a honor for non-academic work (the later are called honorary degrees, or degrees honoris causa). A person issued a
degree is permitted to place initials after their name indicating the award, and in some cases (Doctorates and Higher Doctorates) assume the title of Doctor (by custom
people with doctorates honoris causa do not assume this title).
Medicine
The term is used to specify levels of burns, ranging from first degree burns to third degree burns.
Music
See: Degree (music).
|