A centimetre or centimeter (US/Philippine spelling), with SI symbol cm, is a unit of length in the International System of Units (SI) equal to one hundredth of a metre, centi being the SI prefix for a factor of 1/100. Equivalently, there are 100 centimetres in 1 metre. The centimetre was the base unit of length in the now deprecated centimetre–gram–second (CGS) system of units.
| centimetre | |
|---|---|
 A carpenter's ruler with centimetre divisions | |
| General information | |
| Unit system | SI |
| Unit of | length |
| Symbol | cm |
| Conversions | |
| 1 cm in ... | ... is equal to ... |
| millimetres | 10 mm |
| imperial & US system | ~0.3937 in |
Though for many physical quantities, SI prefixes for factors of 103—like milli- and kilo-—are often preferred by technicians, the centimetre remains a practical unit of length for many everyday measurements; for instance, human height is commonly measured in centimetres. A centimetre is approximately the width of the fingernail of an average adult person.
Equivalence to other units of length
| 1 centimetre | = 10 millimetres |
| = 0.01 metres | |
| = 0.39370078740157477 inches (There are exactly 2.54 centimetres in one inch.) |
One millilitre is defined as one cubic centimetre, under the SI system of units.
Other uses
In addition to its use in the measurement of length, the centimetre is used:
- sometimes, to report the level of rainfall as measured by a rain gauge
- in the CGS system, the centimetre is used to measure capacitance, where 1 cm of capacitance = 1.113×10−12 farads
- in maps, centimetres are used to make conversions from map scale to real world scale (kilometres)
- to represent second moment of areas (cm4)
- as the inverse of the Kayser, a CGS unit, and thus a non-SI metric unit of wavenumber: 1 kayser = 1 wave per centimetre; or, more generally, (wavenumber in kaysers) = 1/(wavelength in centimetres). The SI unit of wavenumber is the inverse metre, m−1.
Unicode symbols
For the purposes of compatibility with Chinese, Japanese and Korean (CJK) characters, Unicode has symbols for:
- centimetre – U+339D ㎝ SQUARE CM
- square centimetre – U+33A0 ㎠ SQUARE CM SQUARED
- cubic centimetre – U+33A4 ㎤ SQUARE CM CUBED
These characters are each equal in size to one Chinese character and are typically used only with East Asian, fixed-width CJK fonts.
See also
- Conversion of units
- Orders of magnitude (length)
- Reciprocal length
References
- "Decimal multiples and submultiples of SI units". Bureau International des Poids et Mesures. 2014. Retrieved 5 July 2015.
- "Using the BMI-for-Age Growth Charts". cdc.gov. Centers for Disease Control. Archived from the original on 30 January 2014. Retrieved 5 July 2014.
- Price, Beth; et al. (2009). MathsWorld Year 8 VELS Edition. Australia: MacMillan. p. 626. ISBN 978-0-7329-9251-4.
- "Rain Measurement". www.weathershack.com.
- Weisstein, Eric W. "Capacitance -- from Eric Weisstein's World of Physics". scienceworld.wolfram.com.
- CJK Compatibility excerpt from The Unicode Standard, Version 10.0.
External links
- CM to Inch Converter
A centimetre or centimeter US Philippine spelling with SI symbol cm is a unit of length in the International System of Units SI equal to one hundredth of a metre centi being the SI prefix for a factor of 1 100 Equivalently there are 100 centimetres in 1 metre The centimetre was the base unit of length in the now deprecated centimetre gram second CGS system of units centimetreA carpenter s ruler with centimetre divisionsGeneral informationUnit systemSIUnit oflengthSymbolcmConversions1 cm in is equal to millimetres 10 mm imperial amp US system 0 3937 inLook up centimetre in Wiktionary the free dictionary Different lengths as in respect to the electromagnetic spectrum measured by the metre and its derived scales The microwave is in between 1 meter to 1 millimeter Though for many physical quantities SI prefixes for factors of 103 like milli and kilo are often preferred by technicians the centimetre remains a practical unit of length for many everyday measurements for instance human height is commonly measured in centimetres A centimetre is approximately the width of the fingernail of an average adult person Equivalence to other units of length1 centimetre 10 millimetres 0 01 metres 0 39370078740157477 inches There are exactly 2 54 centimetres in one inch One millilitre is defined as one cubic centimetre under the SI system of units Other usesIn addition to its use in the measurement of length the centimetre is used sometimes to report the level of rainfall as measured by a rain gauge in the CGS system the centimetre is used to measure capacitance where 1 cm of capacitance 1 113 10 12 farads in maps centimetres are used to make conversions from map scale to real world scale kilometres to represent second moment of areas cm4 as the inverse of the Kayser a CGS unit and thus a non SI metric unit of wavenumber 1 kayser 1 wave per centimetre or more generally wavenumber in kaysers 1 wavelength in centimetres The SI unit of wavenumber is the inverse metre m 1 Unicode symbolsFor the purposes of compatibility with Chinese Japanese and Korean CJK characters Unicode has symbols for centimetre U 339D SQUARE CM square centimetre U 33A0 SQUARE CM SQUARED cubic centimetre U 33A4 SQUARE CM CUBED These characters are each equal in size to one Chinese character and are typically used only with East Asian fixed width CJK fonts See alsoConversion of units Orders of magnitude length Reciprocal lengthReferences Decimal multiples and submultiples of SI units Bureau International des Poids et Mesures 2014 Retrieved 5 July 2015 Using the BMI for Age Growth Charts cdc gov Centers for Disease Control Archived from the original on 30 January 2014 Retrieved 5 July 2014 Price Beth et al 2009 MathsWorld Year 8 VELS Edition Australia MacMillan p 626 ISBN 978 0 7329 9251 4 Rain Measurement www weathershack com Weisstein Eric W Capacitance from Eric Weisstein s World of Physics scienceworld wolfram com CJK Compatibility excerpt from The Unicode Standard Version 10 0 External linksCM to Inch Converter
