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science/physics/SI Units.md

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-obj: meta/collection
+obj: concept
+wiki: https://en.wikipedia.org/wiki/International_System_of_Units
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-#wip #🐇 #notnow 
+# SI Units
+The International System of Units (SI) is a modern metric system that is widely used in [science](../Science.md), technology, and engineering. It was developed to provide a consistent and coherent framework for measuring physical quantities, and it includes seven base units and several derived units.
+
+## Base Units:
+The seven base units of the SI system are:
+- [Meter](units/Meter.md) (m) - length
+- [Kilogram](units/Kilogram.md) (kg) - mass
+- [Second](units/Second.md) (s) - time
+- [Ampere](units/Ampere.md) (A) - electric current
+- [Kelvin](units/Kelvin.md) (K) - thermodynamic temperature
+- [Mole](units/Mole.md) (mol) - amount of substance
+- [Candela](units/Candela.md) (cd) - luminous intensity
+
+## Prefixes
+The SI system uses prefixes to represent multiples and submultiples of the base units. Here are some common prefixes used in the SI system:
+
+| Prefix | Symbol | Multiple       |
+| ------ | ------ | -------------- |
+| atto   | `a`    | $$ 10^{-18} $$ |
+| femto  | `f`    | $$ 10^{-15} $$ |
+| pico   | `p`    | $$ 10^{-12} $$ |
+| nano   | `n`    | $$ 10^{-9} $$  |
+| micro  | `μ`    | $$ 10^{-6} $$  |
+| milli  | `m`    | $$ 10^{-3} $$  |
+| centi  | `c`    | $$ 10^{-2} $$  |
+| deci   | `d`    | $$ 10^{-1} $$  |
+| Base   | -      | $$ 10^{0} $$   |
+| deca   | `da`   | $$ 10^{1} $$   |
+| hecto  | `h`    | $$ 10^{2} $$   |
+| kilo   | `k`    | $$ 10^{3} $$   |
+| mega   | `M`    | $$ 10^{6} $$   |
+| giga   | `G`    | $$ 10^{9} $$   |
+| tera   | `T`    | $$ 10^{12} $$  |
+| peta   | `P`    | $$ 10^{15} $$  |
+| exa    | `E`    | $$ 10^{18} $$  |
+| zetta  | `Z`    | $$ 10^{21} $$  |
+
+## Derived Units
+### Electricity
 - [Volt](units/Volt.md)