Current,Voltage and Potential difference

By Nirmal -
Current :
The rate of flow of electrons through a circuit is defined as current . In general current is denoted with "I or i".The unit of current is coulombs/sec which is called as "amperes(A)".

Voltage or Potential:
Voltage is measure of the work required to move charge from one point to another in electric field. Its unit is Joules/Coloumb called as Volt (V). V=w/q.

Potential difference :
(i) the difference in electrical potential between two points in a circuit expressed in volts(V).
(ii) the difference in electrical charge between two points in a circuit expressed in volts(V).

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