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Current Electricity

Understand what Current Electricity is, the SI unit of current electricity, types, and the difference between direct current and alternating current.

Introduction

Over the past centuries, several discoveries have been made to simplify human lives; one such invention which changed the way people live was current electricity that brought storms into everyone’s lives. The man behind this incredible invention is Benjamin Franklin.

In this article, we will explain one of the most crucial chapters of physics, Current Electricity, and topics related to it.

What is Current Electricity?

Introduced by Benjamin Franklin, current electricity is one discovery on which humans are highly dependent on meeting everyday requirements. Current electricity can be defined as the total time electrons flow from one circuit point. I is used to denote the current electricity.

I = q/t = total charge/charge

Instantaneous current Iinstant = dq/dt

Here dq is small charge

dt is short time interval

The most prominent example of the electric current is lightning, where the charge flows from the sky to the earth and produces a current known as the transient current. As soon as the charge flow stops, the current also ceases. Apart from this, torches and clocks are the most common examples of current electricity.

SI unit of the Electric Current

The SI unit of the electric current is Amperes, denoted by A. Where I = q/t = 1 Coulomb/sec = 1 A.

This is why the current flowing from the current-carrying wires is one ampere. Ampere is one of the seven fundamental units in physics.

Types of Current Electricity

There are mainly two types of current electricity which are-

Direct current is also known as DC
Alternating current is also known as AC

Let’s understand each of these in detail-

Direct Current

When the direction of the current electricity remains constant, it is termed as direct current. It can be defined by the regular flow of electrons that flow from the region of the higher density to the lower electron density. DC can be commonly found in almost all electric appliances used at home.

Alternating Current

The next type of current electricity is the alternating current, where the direction of the current electricity keeps on changing. This occurs due to regular fluctuation in the voltage leading to periodic back for the current. Of the two, alternating current is the most preferred current electricity used in household equipment.

Difference Between Direct Current and Alternating Current

Below, we have listed the significant differences between the direct current and alternating current in a tabular form for better understanding. Let’s have a look-

Alternating Current AC	Direct Current DC
Alternating current is a safer option for transferring long distances without losing electric power.	On the other hand, the direct current is not suitable for travelling a long distance as it loses electric power.
The magnets rotating around are responsible for the change in the flow of electric current.	Since the magnetism is steady, there’s no change in the direction of the flow of electric current.
The frequency of the alternating current is heavily dependent on the country. However, in general, the frequency remains around 50 Hz to 60 Hz.	Direct current has absolutely no frequency.
In AC, the current changes its flow and direction to the backward at regular intervals.	In the case of DC, there is no change in the flow of the direction.
The electors present in alternating current keep changing their directions from backwards to forward.	In direct current, the electrons only move in the forward direction.

Generation of Current Electricity

There are several methods by which the current electricity can be generated. These are as follows-

Suppose a metal wire is moved through a magnetic field. By doing this, both direct current and alternating current can be generated in the least amount of time possible.

By performing chemical reactions using a battery. Using this method, only the direct current or the DC can be generated.

Define Static Electricity

Static electricity can be defined as the electric charge which builds up only on the surface of substances or materials. Until these charges are discharged or grounded, they remain static. The primary reason why static electricity is formed is due to fiction. Every time the negative and the positive charges are separated, it gives rise to a phenomenon known as static electricity.

Difference Between Current Electricity and Static Electricity

Below, we have highlighted the difference between Current Electricity and static electricity in a tabular form to help you understand these in detail. Let’s have a look.

Current Electricity	Static Electricity
Current electricity can be defined as the total time electrons flow from one circuit point. I donate the current electricity.	Static electricity can be defined as the electric charge which builds up only on the surface of substances or materials.
Batteries and power plants are the primary reasons for generating the current electricity.	Every time an object is rubbed against one another, it tends to transfer charge resulting in the development of static electricity.
Current Electricity can be controlled	Static Electricity cannot be controlled
The most prominent example of current electricity is the electronic devices that require electricity.	Every time you touch a doorknob and experience sudden shock is static electricity.

Conclusion

In this article we study about the electric current and different aspect of electric current. Electric current is defined as charge flow in per unit time. Electric current are of two types such that alternative current and direct current.