Why electric current is a SI base unit?

In summary, the SI unit for electric current is the ampere, not the coulomb, due to the need for base units to be realizable and portable. While there are proposals to redefine the system in the future, the current base unit will remain the ampere due to bureaucratic inertia.
  • #1
wasi-uz-zaman
89
1
hi, why electric current is a SI base unit - why not couloumb?
 
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  • #2
Wikipedia explains it quite well.
 
  • #3
wasi-uz-zaman said:
hi, why electric current is a SI base unit - why not couloumb?
In the past, realizability. A system of units needs to have base units that are realizable and portable. How do you measure charge? A flowing current induces a force on the wires through which the current is flowing. That force is measurable (but there are better realizations).

In the future, it's a bit fuzzier. The proposed change to the International System makes the elementary charge (the charge of one electron) a defined constant, exactly 1/(6.2415093×1018) coulombs (or something to that effect). The ampere will be defined in terms of a current that has specific number of elementary charges flowing past a point per second. So which is the base unit now, the ampere or the coulomb? It's still the ampere. The reason: Because they said so. Bureaucratic inertia is an incredibly powerful force, even though it cannot be expressed in Newtons.
 

Related to Why electric current is a SI base unit?

Why is electric current a SI base unit?

Electric current is considered a SI base unit because it is one of the fundamental physical quantities that can be measured and expressed in terms of other units. It is also an essential quantity for understanding and describing many natural phenomena.

What is the definition of electric current?

Electric current is the flow of electric charge through a conductor. It is measured in units of amperes (A) and is defined as the rate of flow of one coulomb of charge per second.

Why is amperage used to measure electric current?

Amperage is used to measure electric current because it is a standard unit of measurement in the SI system and is based on the fundamental unit of charge, the coulomb. It is also a practical unit for measuring the flow of electric current in everyday applications.

What are the advantages of using electric current as a base unit?

Using electric current as a base unit allows for easier conversion between units of measurement, as it is a fundamental quantity that can be expressed in terms of other units. It also provides a consistent and standardized system for measuring and describing electrical phenomena.

Can electric current be measured in other units?

Yes, electric current can be measured in other units such as milliamperes (mA) or kiloamperes (kA). However, the SI unit of amperes is the most commonly used and recognized unit for measuring electric current.

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