4.2.2 Electric Current

Electric current is the rate of flow of electric charge. It's a fundamental concept in electricity and is measured in Amperes (A).

What is Electric Current?

Imagine a pipe carrying water. The electric current is like the amount of water flowing through the pipe per unit time. It represents the quantity of electric charge passing a point in a circuit per second.

Definition

Electric current (I) is defined as the amount of electric charge (Q) passing a given point in a circuit per unit time (t).

Mathematically, this is expressed as:

$$I = \frac{Q}{t}$$

Where:

• I is the electric current measured in Amperes (A)
• Q is the electric charge measured in Coulombs (C)
• t is the time measured in seconds (s)

Units of Electric Current

The SI unit for electric current is the Ampere (A). One Ampere is defined as the flow of one Coulomb of charge per second.

How Current is Related to Charge

The amount of electric current is directly proportional to the amount of charge flowing. More charge flowing per second means a larger current.

Table Summary

Quantity	Symbol	Unit
Electric Current	I	Ampere (A)
Electric Charge	Q	Coulomb (C)
Time	t	Second (s)

Key takeaway: Electric current is a measure of how much electric charge is moving. The more charge moving, the greater the current.