In 1960 adopted the International System of Units - IS (International System). For needs of science and technology this system entered 7 main units: meter, kilogram, second, ampere, mol, kelvin and candela, and also their derivatives. Units of measure, identical to the whole world, in many respects facilitated mutual understanding of scientific all countries. Difficulties arise only when the value of sizes is more or less, than it is accepted SI. And it meets often. For example, it is more convenient to measure the area of the territory of the countries in square kilometers, and the cross-sectional area of an electric cable in square millimeters.
It is required to you
- Ability to make arithmetic actions with degrees
Instruction
1. For transfer of square millimeters to square meters take a closer look at the word "millimeter" more attentively. It consists of two parts. The root "meter" is unit of length SI. The prefix "miles-", means a thousand part something, and is alphabetic record of a decimal multiplier: 0.001 or 10^-3. Conditionally write down it so: 1 mm =10^-3м. Thus any length expressed in millimeters can be presented in the following form: Hmm = X•10^-3 m. For example: 27 mm =27•10^-3m.
2. The square millimeter is the millimeter increased by millimeter, or 10^-3м squared: мм^2 = (10^-3) ^2 ¼^2=10^ (-3 ·2) м^2=10^-6м^2. I.e. instead of the first letter "m" (mile-) write "10^-6" and all. For example: 51мм^2 = 51 • (10^-3) ^2 m^2=51•10^-6 м^2.
3. By the same method you lead to SI not only millimeters in a square, but also cubed, and in any other degree. For example: (394mm^3=394•10^-3) ^3 m^3=394•10^-9 м^3, (68mm^-6=68•10^-3m) ^-6 m^-6=68•10^18 м^-6.
4. This way you transfer to various degrees and other submultiple and multiple sizes of meter. For example: (79sm^3=79•10^-2m) ^3 m^3=79•10^-6 м^3, 422 (km^2=422•10^3m) ^2 m^2=422•10^6 м^2.