Usually, the order of magnitude refers to a series of 10 power That is, the ratio between two adjacent orders of magnitude is 10. For example, two numbers differ Three orders of magnitude, in fact, means that one number is 1000 times larger than the other. The following table describes the order of magnitude in decimal.
number | Scientific notation | Order of magnitude |
|---|
zero point zero zero one | 10^-3 | −3 |
zero point zero one | 10^-2 | −2 |
zero point one | 10^-1 | −1 |
one | 10^0 | zero |
ten | 10^1 | one |
one hundred | 10^2 | two |
one thousand | 10^3 | three |
ten thousand | 10^4 | four |
The order of magnitude of a number is the power of 10 it contains. It is precisely defined as the power of its common logarithm integer part. For example, the logarithm of 4000000 is 6.602, and its order of magnitude is 6. It can be said that the order of magnitude of a number is its approximate position on the logarithmic scale. The order of magnitude estimation of an unknown quantity is to estimate the nearest power of 10. For example, an unknown quantity (such as the number of people on the earth) between 3 billion and 30 billion can be estimated as 10.
The difference of the order of magnitude between two quantities is a multiple of 10. For example, the mass of Saturn is 95 times that of the Earth, that is, the mass of Saturn is two orders of magnitude greater than that of the Earth.
Common order of magnitude
There are many different ways to classify things in the physical world, one of which is to compare their sizes. The following part of this article includes a list of things of the same order of magnitude (time, length, area, volume, mass and energy), which is very helpful to understand the relative size of things and the approximate size of the universe. We will use SI units and their prefixes: these units contain orders of magnitude concept 。 International System of Units （ SI ）Prefix Represents multiples and fractions of units. Most are multiples or fractions of thousands. [2] According to《 Legal measurement unit of the People's Republic of China 》It is stipulated that the prefixes used in China are as follows. The words in brackets can be omitted without confusion. (10 ^ 24 means 10 to the 24th power) Multiples and fractions | Prefix | Symbol | english |
10^24 | Yao | Y | Yotta |
10^21 | Ze | Z | Zetta |
10^18 | Ai (Kesa) | E | Exa |
10^15 | Pat | P | Peta |
10^12 | Too | T | Tera |
10^9 | Ji (coffee) | G | Giga |
10^6 | Mega | M | Mega |
10^3 | thousand | k | kilo |
10^2 | hundred | h | hecta |
10^1 | ten | da | deca |
10^-1 | branch | d | deci |
10^-2 | Per cent | c | centi |
10^-3 | Millionth | m | milli |
10^-6 | tiny | μ | micro |
10^-9 | Na | n | nano |
10^-12 | Pi (Ke) | p | pico |
10^-15 | Fly (female bracket) | f | femto |
10^-18 | Ato | a | atto |
10^-21 | Chek (Putuo) | z | zepto |
10^-24 | One (Cotto) | y | yocto |
