Length

From Free net encyclopedia

This article is about the concept and measurement of distance. For usage in cricket, see line and length.

In general English usage, length (symbols: l, L) is one particular instance of distance: an object's length is its extent along its longest dimension. This is to be contrasted with height, denoting vertical extent, and width (or breadth), denoting a lateral extent along a dimension shorter than an object's length. In the physical sciences and engineering, the word "length" is typically used synonymously with "distance".

Length is the metric of one dimension of space. The metric of ordinary three-dimensional space 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. 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.