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For other uses, see Mega (disambiguation).
Mega- (symbol M) is an prefix in the metric system denoting a factor of million (106 or 1000000). Confirmed in 1960, it comes from the Greek μέγας, meaning great.[1]
Contents
Other common examples of usage
- megapixel - 1 million pixels in a digital camera
- one megatonne (of TNT) (a unit often used in measuring the explosive power of nuclear weapons) is the approximate energy released on igniting one million tonnes of TNT.
- megahertz — frequency of electromagnetic radiation for radio and television broadcasting, GSM, etc. 1 MHz = 1,000,000 Hz.
Exponentiation
When units occur in exponentiation, such as in square and cubic forms, any size prefix is considered part of the unit, and thus included in the exponentiation.
- 1 Mm2 means one square megametre or the size of a square of 1,000,000 m by 1,000,000 m or 1012 m2, and not 1,000,000 square metres (106 m2).
- 1 Mm3 means one cubic megametre or the size of a cube of 1,000,000 m by 1,000,000 m by 1,000,000 m or 1018 m3, and not 1,000,000 cubic metres (106 m3)
Computing
In computing, mega can sometimes denote 1,048,576 (220) of information units (example: a megabyte, a megaword), but can denote 1,000,000 (106) of other quantities, for example, transfer rates: 1 megabit/s = 1,000,000 bit/s.
The prefix mebi has been suggested as a prefix for 220 to avoid ambiguity.
SI prefixes Prefix Symbol 1000m 10n Decimal Short scale Long scale Since[n 1] yotta Y 10008 1024 1000000000000000000000000 Septillion Quadrillion 1991 zetta Z 10007 1021 1000000000000000000000 Sextillion Trilliard 1991 exa E 10006 1018 1000000000000000000 Quintillion Trillion 1975 peta P 10005 1015 1000000000000000 Quadrillion Billiard 1975 tera T 10004 1012 1000000000000 Trillion Billion 1960 giga G 10003 109 1000000000 Billion Milliard 1960 mega M 10002 106 1000000 Million 1960 kilo k 10001 103 1000 Thousand 1795 hecto h 10002/3 102 100 Hundred 1795 deca da 10001/3 101 10 Ten 1795 10000 100 1 One – deci d 1000−1/3 10−1 0.1 Tenth 1795 centi c 1000−2/3 10−2 0.01 Hundredth 1795 milli m 1000−1 10−3 0.001 Thousandth 1795 micro μ 1000−2 10−6 0.000001 Millionth 1960 nano n 1000−3 10−9 0.000000001 Billionth Milliardth 1960 pico p 1000−4 10−12 0.000000000001 Trillionth Billionth 1960 femto f 1000−5 10−15 0.000000000000001 Quadrillionth Billiardth 1964 atto a 1000−6 10−18 0.000000000000000001 Quintillionth Trillionth 1964 zepto z 1000−7 10−21 0.000000000000000000001 Sextillionth Trilliardth 1991 yocto y 1000−8 10−24 0.000000000000000000000001 Septillionth Quadrillionth 1991 See also
- SI prefix
- Binary prefix
- Mebibyte
- Orders of magnitude
References
- ^ "[http://dictionary.oed.com/cgi/entry/00304790 mega-]". Oxford English Dictionary. Oxford University Press. 2nd ed. 1989.
External links
Categories:- SI prefixes
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