Length
From Wikipedia, the free encyclopedia.
In general English usage,
length (symbols:
l,
L) is but one particular instance of
distance – an object's
length is how
long the object is – but in the physical sciences and engineering, the word
length is in some contexts used synonymously with "
distance".
Height is vertical distance;
width (or
breadth) is a lateral distance; an object's width is less than its length. No one speaks of "the length from here to
Alpha Centauri", but rather of "the distance from here to
Alpha Centauri," but when one speaks of distance more abstractly, one says "A
kilometre or a mile, is a unit of
length" or "...of distance", and the two statements are synonymous. Likewise, a
mountain might be a mile in height. Length is the
metric of one
dimension of
space. The metric of space itself is
volume, or (length)
3. Length is commonly considered to be one of the
fundamental units, meaning that it cannot be defined in terms of other dimensions. However, a set of units can be constructed where units of length can be derived from fundamental physical constants - see
Planck units and
Planck length.
Colloquially length sometimes refers to duration, especially when used in context of music.
The
SI unit of Length is the
metre (U.S. spelling: meter), from which can be derived:
Other units of length
See also
External links
