A 'decametre' (
American spelling: 'decameter', symbol 'dam') is a very rarely used
unit of
length in the
metric system, equal to ten
metres, the current
SI base unit of length. It can be written in
scientific notation as 1 E+1 m (exponential notation) — meaning 10 × 1 m. The "c" is pronounced as a "k", unlike in decimetre.
nanometre <<<
micrometre <<<
millimetre <
centimetre <
decimetre <
metre <
decametre <
hectometre <
kilometre
This measure is included mostly for completeness. One of the few practical uses of the decameter is for altitude of
geopotential heights (circumscribing equal pressure) in meteorology. Interestingly, meteorologists also use another seldom encountered SI prefix:
hecto- in hectopascal (hPa).
★ For
surface the 'square decametre' ('dam
2') is a common unit, be it by the name
are ('a'). The 'are' is a measurement of area the size of 1
decametre by 1 decametre — the square decametre — 10 metres by 10 metres, equalling 100
square metres ('100 m
2').
★ For
volumes the 'cubic decametre' ('dam
3') is also used, 10 m by 10 m by 10 m equalling 1,000
cubic metres ('1,000 m
3').
See also
★
SI
★
SI prefix
★
deca-
★
Metric system
★ For length:
1 E+1 m and
Orders of magnitude (length)
★ For surface:
1 E+2 m² and
Orders of magnitude (area)
★ For volume:
1 E+3 m³ and
Orders of magnitude (volume)
★
Conversion of units, for comparison with other units