Question

derive the expression for electric current

Answer 1

Electric current is the rate of flow of charge,
I= Q/t

And from Ohm's law:-
V is directly proportional to the I ,
V=IR
I=V/R

Answer 2

1)Electric current is the rate of flow of charge and Electric current in terms of number of electrons = 1 = Q/t.

2)Electric circuit is a continuous pathway for the current to flow which has electrical components.