Electric Current

Electric current is expressed by the amount of charge flowing through a particular area in unit time. 
In other words, it is the rate of flow of electric charges.
Electric Current bulb battery charge potential difference ampere voltage

So, If a net charge Q, flows across any cross-section of a conductor in time t, then the current I, through the cross-section is
Electric Current (I) = Electric charge (Q) / Time (t)
           I=Q/t
Where, I is Electric Current
             Q is Electric Charge
       and t is time.
The SI unit of electric charge is coulomb (C), which is equivalent to the charge contained in nearly 6 × 1018 electrons.
The SI unit of electric Current is Ampere(A).
The dimensional formula for Current is



                                     I= [M0L0T−1Q]
An instrument called ammeter measures electric current in a circuit. It is always connected in series in a circuit through which the current is to be measured.