Why is charge a derived quantity

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Why is charge a derived quantity?
 
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There are seven base units from which all other units are derived.


-meter (length)
-kilogram (mass)
-second (time)
-ampere (electric current)
-kelvin (temperature)
-candela (luminous intensity)
-mole (concentration of substance)

Electric charge is measured in Coulombs, or Amperes seconds.
 
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In SI, current is a fundamental unit (ampere) and charge is a derived unit (coulomb = ampere · second) for practical reasons. It's easier to implement the standard for current precisely, by measuring the force between two current-carrying wires, than it would be to implement a standard for charge precisely, involving something like measuring the force between two charges, or counting electrons.
 


AlephZero said:
Ampere seconds, not amperes per second.

My apologies.
Edited and corrected.
 
No prob. Thanks for that. Really cleared it up