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A metric foot is a nickname occasionally used in the United Kingdom for a length of 300 millimetres (30 cm). The 30 cm metric ruler was of a similar length to the traditional 12-inch (one foot) ruler, so hence the term 'metric foot'. A metric foot can be divided into twelve "metric inches" of 25 millimetres (2.5 cm) each. The (short) metric foot and inch are therefore 4.8 and 0.4 millimetres (or about ) shorter than an imperial foot and inch respectively. The term "metric foot" does not appear in any British Standard, but the construction industry uses multiples of 300 mm and 600 mm as preferred dimensions as per the international standard on modular coordination, ISO 2848. These numbers were chosen because of their large number of divisors - any multiple of 600 mm can be evenly divided into 2, 3, 4, 5, 6, 8, 10, 12, 15, 20, 24, 25, 30, etc. parts. While the term "metric foot" is still occasionally used in the United Kingdom, in particular in the timber trade, dimensions are most likely to be quoted exclusively in metric units today. The sizes of the studios at BBC Television Centre in London, which opened in 1960, are specified and measured in metric feet—a contrast to film stages where imperial feet and inches prevail. Historically in France, under the ''mesures usuelles'' system (intermediary between traditional French units and metric units), a (long) metric foot was exactly a third of a metre ( mm). As metric utilizes a powers of 10 motif, one approach to the metric foot is to set it as the geometric mean of the two above usages (30cm & 1/3m), or the m. The following compares the relative lengths of the short metric foot (smf), the imperial foot, the geometric mean metric foot (mf), and the long metric foot (lmf), left to right, respectively. == See also == * Tonne (metric ton) * Metric mile 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Metric foot」の詳細全文を読む スポンサード リンク
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