A 'scale factor' is a number which
scales, or multiplies, some quantity. In the equation
,
is the scale factor for
.
is also the
coefficient of
, and may be called the
constant of proportionality of
to
. For example, doubling distances corresponds to a scale factor of 2 for distance.
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:
.
★ 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:
.
★ The
volume of a shape in three-space is equal to the
cube of the scale factor times the initial volume. In other words:
.
★ The scale factor also scales the
coordinates of the
centroid of a shape.
★ The
inverse of scaling a shape is scaling it again, with the
reciprocal of the first factor.
See also
★
Scale (ratio)
★
Scale (map)
★
Scales of scale models
★
Scale (disambiguation)
★
Scaling (geometry)
★
Scalar (mathematics)
★
★
Scale Factor