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Scale factor

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A scale factor is a number which scales, or multiplies, some quantity. In the equation Failed to parse (Missing texvc executable; please see math/README to configure.): y=Cx , Failed to parse (Missing texvc executable; please see math/README to configure.): C

is the scale factor for Failed to parse (Missing texvc executable; please see math/README to configure.): x

. Failed to parse (Missing texvc executable; please see math/README to configure.): C

is also the coefficient of Failed to parse (Missing texvc executable; please see math/README to configure.): x

, and may be called the constant of proportionality of Failed to parse (Missing texvc executable; please see math/README to configure.): y

to Failed to parse (Missing texvc executable; please see math/README to configure.): x

. For example, doubling distances corresponds to a scale factor of 2 for distance.

Contents

Applications

There is also a scale factor for the expansion of the Universe.

Computer Science

Scale factors are used in computer science when certain real world numbers need to be represented on a different scale in order to fit a required number format. See Scale Factor (Computer Science).

Geometry

A factor can be used to scale shapes in 1, 2, or 3 dimensions (and conceptually even more.) There are a few interesting properties of scaling which are relevant:

  • The length of a line that is scaled is the previous length times the scale factor. In other words:

Failed to parse (Missing texvc executable; please see math/README to configure.): L_1 = L_0 \cdot c .

  • The area of a shape in two-space (a circle, for example) is equal to the previous area times the square of the scale factor. In other words:

Failed to parse (Missing texvc executable; please see math/README to configure.): A_1 = A_0 \cdot c^2 .

  • The volume of a shape in three-space is equal to the cube of the scale factor times the initial volume. In other words:

Failed to parse (Missing texvc executable; please see math/README to configure.): V_1 = V_0 \cdot c^3 .

See also

es:Factores de escala

pl:Czynnik skali

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