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The word 'current' is defined as the

**flow of particles**in a particular direction. For example, air currents cause winds, water currents, etc. Likewise, electric current is the flow of electric charges through a particular area in unit time.*Water currents*

An electric current is generated by the motion of electric charges (electrons) through any conductor like copper wire. In other words, moving electrons generate an electric current.

*The flow of electrons in a circuit*

Have you ever noticed a river flowing through the channel or pathway while travelling on the outskirts of the city?

*A river channel*

When you observe a river channel, you can easily notice that the water flows from a higher level to a lower level.

Even air moves from a high-pressure region to a low-pressure region, thus creating winds. Likewise, in an electric circuit, the charges also flow in the same manner.

Unit of electric current:

Electric current or simply current is denoted by the symbol '\(I\)'. It is the total amount of charges flowing in a cross-section of a conductor in unit time.*Flow of charges in a conductor*

If a net charge (\(Q\)) flows through any cross-section area of a conductor in unit time (\(t\)), then the current (\(I\)) flowing through the conductor is given as,

$\begin{array}{l}\mathit{Current}=\frac{\mathit{Charge}}{\mathit{Time}}\\ \\ I=\frac{Q}{t}\end{array}$

Electric current is a scalar quantity. The SI unit of the electric current is ampere (\(A\)). The unit 'ampere' is named after Andre-Marie Ampere, a French scientist.

One ampere is defined as the amount of current flowing through any cross-section of a conductor when one coulomb of charge flows through it in one second.

Mathematically,

$\begin{array}{l}1\phantom{\rule{0.147em}{0ex}}\mathit{ampere}=\phantom{\rule{0.147em}{0ex}}\frac{1\phantom{\rule{0.147em}{0ex}}\mathit{coulomb}}{1\phantom{\rule{0.147em}{0ex}}\mathit{second}}\\ \\ 1\phantom{\rule{0.147em}{0ex}}A=\phantom{\rule{0.147em}{0ex}}\frac{1\phantom{\rule{0.147em}{0ex}}C}{1\phantom{\rule{0.147em}{0ex}}s}\end{array}$

**Other units in ampere:**

There are some other units of ampere listed in the table below.

Units | Symbols | In ampere |

kiloampere | \(kA\) | \(10^3 A\) |

Megaampere | \(MA\) | \(10^6 A\) |

milliampere | \(mA\) | \(10^{-3} A\) |

microampere | \(\mu A\) | \(10^{-6} A\) |