What is Electric Current? Formula & Definition of Electric Current

What is Electric Current? Formula & Definition of Electric Current.

Electric current is the flow of charge (charged particles) through a conductor with respect to time. The process is similar to flowing of a river in one direction.

How is Electric Current Produced?

Electron flow is in the opposite direction from negative to positive. Electric current flows in the direction of positive charge i.e positive to negative.

In a circuit, flow of positive current is marked by an arrow. In a conductor metal like copper or aluminum, only negatively charged free electrons move to produce current.

Positively charged protons can not move. But in a gas or liquid, both the protons (+) and electrons (–) move to produce a flow of current.

How is Electric Current Measured and What is its Unit?

Electric current is measured by the number of “free electrons” passing a particular point in a circuit per second. So we can conclude and define electric current as flow of charge per unit second.

The SI unit of charge (not current) is coulomb. 1 coulomb = quantity of electricity carried in 1 second by a current of 1 ampere.

The SI (International System of Units) unit of current is the ampere (A). A constant current has symbol “I”. Time-varying current has a symbol “i”.

What is Formula to Calculate Electric Current?

A current of one ampere = 1 coulomb of charge passing a given point per second. In general, charge Q is determined by steady current I flowing for a time t as Q = It.

Charge-Current Formula