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The word 'current' is defined as the flow of particles in a particular direction. For example, air currents cause winds, ocean currents, etc. Likewise, electric current is the flow of electric charges in a direction.
 
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Ocean currents
An electric current is generated by the motion of electric charges (electrons) through any conductor like copper wire. In other words, moving electrons generate an electric current.
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The flow of electrons in a circuit
 
Have you ever noticed a river flowing through the channel or pathway while travelling on the outskirts of the city?
 
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A river channel
 
When you observe a river channel, you can easily notice that the water flows from a higher level to a lower level.

Even air moves from a high-pressure region to a low-pressure region, thus creating winds. Likewise, in an electric circuit, the charges also flow in the same manner.
 
The direction of charges:
When a conducting path (wire) is provided to a charged object, electrons begin to flow through the path from a higher electric potential to a lower electric potential zone.
 
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Direction of current
 
The direction of the current is always from the positive terminal to the negative terminal of the battery through a conducting wire.
 
Unit of electric current:
Electric current or simply current is denoted by the symbol '\(I\)'. It is the total amount of charges flowing in a cross-section of a conductor in unit time.
 
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The flow of charges in a conductor
  
If a net charge (\(Q\)) flows through any cross-section area of a conductor in unit time (\(t\)), then the current (\(I\)) flowing through the conductor is given as,
 
Current = ChargeTimeI = Qt
 
Electric current is a scalar quantity. The SI unit of the electric current is ampere (\(A\)).
One ampere is defined as the amount of current flowing through any cross-section of a conductor when one coulomb of charge flows through it in one second.
Mathematically,
 
1 ampere = 1 coulomb1 second
 
Other units in ampere:
There are some other units of ampere listed in the table below.
 
Units
Symbols
In ampere
kiloampere
\(kA\)
\(10^3 A\)
Megaampere
\(MA\)
\(10^6 A\)
milliampere
\(mA\)
\(10^{-3} A\)
microampere
\(\mu A\)
\(10^{-6} A\)