Centimetre
A centimetre (international spelling as used by the International Bureau of Weights and Measures; symbol cm) or centimeter (American spelling) is a unit of length in the metric system, equal to one hundredth of a metre, centi being the SI prefix for a factor of 1⁄100. The centimetre was the base unit of length in the now deprecated centimetre–gram–second (CGS) system of units.
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. A centimetre is approximately the width of the fingernail of an average adult person.
Equivalence to other units of length
One cubic centimetre is equal to 1 millilitre, under the current SI system of units.
Other uses
In addition to its use in the measurement of length, the centimetre is used:
33-centimeter band
The 33-centimeter or 900 MHz band is a portion of the UHF radio spectrum internationally allocated to amateur radio on a secondary basis. It ranges from 902 to 928 MHz and is unique to ITU Region 2. It is primarily used for very local communications as opposed to bands lower in frequency. However, very high antennas with high gain have shown 33 centimeters can provide good long range communications almost equal to systems on lower frequencies such as the 70 centimeter band. The band is also used by industrial, scientific, and medical (ISM) equipment, as well as low powered unlicensed devices. Amateur stations must accept harmful interference caused by ISM users but may receive protection from unlicensed devices.
The 900 MHz frequency is also used as a reference band e.g. to express the total power or impact of the electric field "E" - expressed in V/m - or the power density "S" - expressed in W/m2 - of the overall cellular frequencies immision caused by all frequencies s.a. the four bands 850 / 900 / 1,800 / 1,900 MHz - which many GSM phones support and mobile phone operators use - used by all mobile phone operators at the same time to a certain space where e.g. humans are exposed to these frequencies over a certain span of time. More: Mobile phone radiation and health section.
20 centímetros
20 centímetros (English title 20 Centimeters) is a 2005 Spanish film about a narcoleptic transgender woman's life as she works to get the surgery to fix her "20 centímetros" problem. The film was written and directed by Ramón Salazar, and stars Mónica Cervera as Marieta and Pablo Puyol as Raúl, the man who loves "all" of Marieta.
References
External links
Podcasts:
